1211421617316 has 135 divisors (see below), whose sum is σ = 3238198793137. Its totient is φ = 394911784800.

The previous prime is 1211421617249. The next prime is 1211421617327. The reversal of 1211421617316 is 6137161241121.

The square root of 1211421617316 is 1100646.

It is a perfect power (a square), and thus also a powerful number.

1211421617316 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 4 + 2 + 1 + 617 + 31 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1861577316 + 1209560040000 = 43146^2 + 1099800^2 .

It is a super-3 number, since 3×1211421617316³ (a number of 37 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 931145866 + ... + 931147166.

Almost surely, 2^{1211421617316} is an apocalyptic number.

1211421617316 is the 1100646-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211421617316

1211421617316 is an abundant number, since it is smaller than the sum of its proper divisors (2026777175821).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1211421617316 is an frugal number, since it uses more digits than its factorization.

1211421617316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2712 (or 1353 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

Multiplying 1211421617316 by its sum of digits (36), we get a square (43611178223376 = 6603876²).

1211421617316 divided by its sum of digits (36) gives a square (33650600481 = 183441²).

Adding to 1211421617316 its reverse (6137161241121), we get a palindrome (7348582858437).

The spelling of 1211421617316 in words is "one trillion, two hundred eleven billion, four hundred twenty-one million, six hundred seventeen thousand, three hundred sixteen".