20556634 has 16 divisors (see below), whose sum is σ = 35819136. Its totient is φ = 8665200.

The previous prime is 20556619. The next prime is 20556647. The reversal of 20556634 is 43665502.

It is a junction number, because it is equal to n+sod(n) for n = 20556596 and 20556605.

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, 11182 + ... + 12889.

It is an arithmetic number, because the mean of its divisors is an integer number (2238696).

Almost surely, 2^20556634 is an apocalyptic number.

20556634 is a deficient number, since it is larger than the sum of its proper divisors (15262502).

20556634 is a wasteful number, since it uses less digits than its factorization.

20556634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24141.

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 20556634 is about 4533.9424345706. The cubic root of 20556634 is about 273.9369826839.

The spelling of 20556634 in words is "twenty million, five hundred fifty-six thousand, six hundred thirty-four".