1221083136 has 405 divisors, whose sum is σ = 4443303501. Its totient is φ = 322043904.

The previous prime is 1221083131. The next prime is 1221083159. The reversal of 1221083136 is 6313801221.

It is a happy number.

The square root of 1221083136 is 34944.

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

It can be written as a sum of positive squares in only one way, i.e., 180633600 + 1040449536 = 13440^2 + 32256^2 .

It is not an unprimeable number, because it can be changed into a prime (1221083131) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 93929466 + ... + 93929478.

Almost surely, 2^1221083136 is an apocalyptic number.

1221083136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

1221083136 is the 34944-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221083136

1221083136 is an abundant number, since it is smaller than the sum of its proper divisors (3222220365).

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

1221083136 is an equidigital number, since it uses as much as digits as its factorization.

1221083136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 25 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The cubic root of 1221083136 is about 1068.8458560172.

Adding to 1221083136 its reverse (6313801221), we get a palindrome (7534884357).

The spelling of 1221083136 in words is "one billion, two hundred twenty-one million, eighty-three thousand, one hundred thirty-six".