255621520 has 160 divisors (see below), whose sum is σ = 784878336. Its totient is φ = 74956800.

The previous prime is 255621473. The next prime is 255621521. The reversal of 255621520 is 25126552.

It is a super-2 number, since 2×255621520² = 130684722974220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (255621521) 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, 103500 + ... + 105940.

Almost surely, 2^255621520 is an apocalyptic number.

255621520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 255621520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (392439168).

255621520 is an abundant number, since it is smaller than the sum of its proper divisors (529256816).

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

255621520 is a wasteful number, since it uses less digits than its factorization.

255621520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2489 (or 2483 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 28.

The square root of 255621520 is about 15988.1681252106. The cubic root of 255621520 is about 634.6473500190.

The spelling of 255621520 in words is "two hundred fifty-five million, six hundred twenty-one thousand, five hundred twenty".