135621545565231 has 48 divisors (see below), whose sum is σ = 215464279080960. Its totient is φ = 81519325594560.

The previous prime is 135621545565211. The next prime is 135621545565257. The reversal of 135621545565231 is 132565545126531.

135621545565231 is a `hidden beast` number, since 1 + 3 + 5 + 6 + 2 + 1 + 5 + 4 + 556 + 52 + 31 = 666.

It is not a de Polignac number, because 135621545565231 - 2²⁵ = 135621512010799 is a prime.

It is a super-2 number, since 2×135621545565231² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135621545565211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 34324321 + ... + 38071013.

It is an arithmetic number, because the mean of its divisors is an integer number (4488839147520).

Almost surely, 2^{135621545565231} is an apocalyptic number.

135621545565231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

135621545565231 is a deficient number, since it is larger than the sum of its proper divisors (79842733515729).

135621545565231 is a wasteful number, since it uses less digits than its factorization.

135621545565231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3749716 (or 3749713 counting only the distinct ones).

The product of its digits is 16200000, while the sum is 54.

The spelling of 135621545565231 in words is "one hundred thirty-five trillion, six hundred twenty-one billion, five hundred forty-five million, five hundred sixty-five thousand, two hundred thirty-one".