20256420 has 24 divisors (see below), whose sum is σ = 56718144. Its totient is φ = 5401696.

The previous prime is 20256407. The next prime is 20256433. The reversal of 20256420 is 2465202.

It is an interprime number because it is at equal distance from previous prime (20256407) and next prime (20256433).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 168744 + ... + 168863.

It is an arithmetic number, because the mean of its divisors is an integer number (2363256).

Almost surely, 2^20256420 is an apocalyptic number.

20256420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20256420 is an abundant number, since it is smaller than the sum of its proper divisors (36461724).

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

20256420 is a wasteful number, since it uses less digits than its factorization.

20256420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337619 (or 337617 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 20256420 is about 4500.7132768040. The cubic root of 20256420 is about 272.5968906077.

The spelling of 20256420 in words is "twenty million, two hundred fifty-six thousand, four hundred twenty".