20656040 has 32 divisors (see below), whose sum is σ = 48924000. Its totient is φ = 7827264.

The previous prime is 20655997. The next prime is 20656057. The reversal of 20656040 is 4065602.

It is a junction number, because it is equal to n+sod(n) for n = 20655997 and 20656015.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12830 + ... + 14349.

It is an arithmetic number, because the mean of its divisors is an integer number (1528875).

Almost surely, 2^20656040 is an apocalyptic number.

20656040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20656040 is an abundant number, since it is smaller than the sum of its proper divisors (28267960).

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

20656040 is a wasteful number, since it uses less digits than its factorization.

20656040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27209 (or 27205 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 20656040 is about 4544.8916378721. The cubic root of 20656040 is about 274.3778331251.

The spelling of 20656040 in words is "twenty million, six hundred fifty-six thousand, forty".