255561520 has 40 divisors (see below), whose sum is σ = 613353600. Its totient is φ = 98926080.

The previous prime is 255561511. The next prime is 255561557. The reversal of 255561520 is 25165552.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49045 + ... + 54004.

It is an arithmetic number, because the mean of its divisors is an integer number (15333840).

Almost surely, 2^255561520 is an apocalyptic number.

255561520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

255561520 is an abundant number, since it is smaller than the sum of its proper divisors (357792080).

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

255561520 is a wasteful number, since it uses less digits than its factorization.

255561520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103093 (or 103087 counting only the distinct ones).

The product of its (nonzero) digits is 15000, while the sum is 31.

The square root of 255561520 is about 15986.2916275164. The cubic root of 255561520 is about 634.5976908970.

The spelling of 255561520 in words is "two hundred fifty-five million, five hundred sixty-one thousand, five hundred twenty".