1213532555 has 32 divisors (see below), whose sum is σ = 1567157760. Its totient is φ = 899838720.

The previous prime is 1213532513. The next prime is 1213532557. The reversal of 1213532555 is 5552353121.

It is not a de Polignac number, because 1213532555 - 2⁶ = 1213532491 is a prime.

It is a super-2 number, since 2×1213532555² = 2945322524089656050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1213532557) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 767756 + ... + 769334.

It is an arithmetic number, because the mean of its divisors is an integer number (48973680).

Almost surely, 2^1213532555 is an apocalyptic number.

1213532555 is a deficient number, since it is larger than the sum of its proper divisors (353625205).

1213532555 is a wasteful number, since it uses less digits than its factorization.

1213532555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1811.

The product of its digits is 22500, while the sum is 32.

The square root of 1213532555 is about 34835.7941634750. The cubic root of 1213532555 is about 1066.6382260755.

Adding to 1213532555 its reverse (5552353121), we get a palindrome (6765885676).

The spelling of 1213532555 in words is "one billion, two hundred thirteen million, five hundred thirty-two thousand, five hundred fifty-five".