20861672 has 32 divisors (see below), whose sum is σ = 43583400. Its totient is φ = 9295104.

The previous prime is 20861663. The next prime is 20861699. The reversal of 20861672 is 27616802.

It can be written as a sum of positive squares in 4 ways, for example, as 16048036 + 4813636 = 4006^2 + 2194^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 443 + ... + 6474.

Almost surely, 2^20861672 is an apocalyptic number.

It is an amenable number.

20861672 is an abundant number, since it is smaller than the sum of its proper divisors (22721728).

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

20861672 is a wasteful number, since it uses less digits than its factorization.

20861672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6965 (or 6961 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 20861672 is about 4567.4579363142. The cubic root of 20861672 is about 275.2853105016.

The spelling of 20861672 in words is "twenty million, eight hundred sixty-one thousand, six hundred seventy-two".