255577407561 has 24 divisors (see below), whose sum is σ = 429866049600. Its totient is φ = 143288679456.

The previous prime is 255577407541. The next prime is 255577407571. The reversal of 255577407561 is 165704775552.

255577407561 is a `hidden beast` number, since 2 + 5 + 5 + 5 + 7 + 74 + 0 + 7 + 561 = 666.

It is not a de Polignac number, because 255577407561 - 2⁵ = 255577407529 is a prime.

It is a super-2 number, since 2×255577407561² (a number of 24 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 255577407498 and 255577407507.

It is not an unprimeable number, because it can be changed into a prime (255577407511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38268211 + ... + 38274888.

It is an arithmetic number, because the mean of its divisors is an integer number (17911085400).

Almost surely, 2^255577407561 is an apocalyptic number.

255577407561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

255577407561 is a deficient number, since it is larger than the sum of its proper divisors (174288642039).

255577407561 is a wasteful number, since it uses less digits than its factorization.

255577407561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76543165 (or 76543162 counting only the distinct ones).

The product of its (nonzero) digits is 10290000, while the sum is 54.

The spelling of 255577407561 in words is "two hundred fifty-five billion, five hundred seventy-seven million, four hundred seven thousand, five hundred sixty-one".