1211353155 has 24 divisors (see below), whose sum is σ = 2100822048. Its totient is φ = 645703296.

The previous prime is 1211353147. The next prime is 1211353193. The reversal of 1211353155 is 5513531121.

1211353155 is a `hidden beast` number, since 12 + 113 + 531 + 5 + 5 = 666.

It is not a de Polignac number, because 1211353155 - 2³ = 1211353147 is a prime.

It is a super-3 number, since 3×1211353155³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 90634 + ... + 103136.

It is an arithmetic number, because the mean of its divisors is an integer number (87534252).

Almost surely, 2^1211353155 is an apocalyptic number.

1211353155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1211353155 is a deficient number, since it is larger than the sum of its proper divisors (889468893).

1211353155 is a wasteful number, since it uses less digits than its factorization.

1211353155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14667 (or 14664 counting only the distinct ones).

The product of its digits is 2250, while the sum is 27.

The square root of 1211353155 is about 34804.4990626212. The cubic root of 1211353155 is about 1065.9993133016. Note that the first 3 decimals are identical.

Adding to 1211353155 its reverse (5513531121), we get a palindrome (6724884276).

The spelling of 1211353155 in words is "one billion, two hundred eleven million, three hundred fifty-three thousand, one hundred fifty-five".