256021620 has 48 divisors (see below), whose sum is σ = 725948160. Its totient is φ = 67406976.

The previous prime is 256021609. The next prime is 256021621. The reversal of 256021620 is 26120652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256021621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22267 + ... + 31746.

It is an arithmetic number, because the mean of its divisors is an integer number (15123920).

Almost surely, 2^256021620 is an apocalyptic number.

256021620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256021620 is an abundant number, since it is smaller than the sum of its proper divisors (469926540).

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

256021620 is a wasteful number, since it uses less digits than its factorization.

256021620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54104 (or 54102 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 256021620 is about 16000.6756107359. The cubic root of 256021620 is about 634.9782950814.

The spelling of 256021620 in words is "two hundred fifty-six million, twenty-one thousand, six hundred twenty".