256451520 has 112 divisors (see below), whose sum is σ = 876909600. Its totient is φ = 63123456.

The previous prime is 256451519. The next prime is 256451539. The reversal of 256451520 is 25154652.

256451520 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×256451520² = 131534764220620800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2206 + ... + 22754.

It is an arithmetic number, because the mean of its divisors is an integer number (7829550).

Almost surely, 2^256451520 is an apocalyptic number.

256451520 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 256451520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438454800).

256451520 is an abundant number, since it is smaller than the sum of its proper divisors (620458080).

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

256451520 is a wasteful number, since it uses less digits than its factorization.

256451520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20582 (or 20572 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

The square root of 256451520 is about 16014.1037838525. The cubic root of 256451520 is about 635.3335053446. Note that the first 3 decimals are identical.

The spelling of 256451520 in words is "two hundred fifty-six million, four hundred fifty-one thousand, five hundred twenty".