20256680 has 16 divisors (see below), whose sum is σ = 45577620. Its totient is φ = 8102656.

The previous prime is 20256659. The next prime is 20256689. The reversal of 20256680 is 8665202.

It can be written as a sum of positive squares in 2 ways, for example, as 17023876 + 3232804 = 4126^2 + 1798^2 .

It is not an unprimeable number, because it can be changed into a prime (20256689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253169 + ... + 253248.

Almost surely, 2^20256680 is an apocalyptic number.

20256680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20256680 is an abundant number, since it is smaller than the sum of its proper divisors (25320940).

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

20256680 is a wasteful number, since it uses less digits than its factorization.

20256680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506428 (or 506424 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 20256680 is about 4500.7421610219. The cubic root of 20256680 is about 272.5980569028.

The spelling of 20256680 in words is "twenty million, two hundred fifty-six thousand, six hundred eighty".