20438855672 has 16 divisors (see below), whose sum is σ = 38580057000. Its totient is φ = 10150840480.

The previous prime is 20438855651. The next prime is 20438855681. The reversal of 20438855672 is 27655883402.

It is a self number, because there is not a number n which added to its sum of digits gives 20438855672.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8572154 + ... + 8574537.

Almost surely, 2^20438855672 is an apocalyptic number.

It is an amenable number.

20438855672 is a deficient number, since it is larger than the sum of its proper divisors (18141201328).

20438855672 is a wasteful number, since it uses less digits than its factorization.

20438855672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17146846 (or 17146842 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 50.

The spelling of 20438855672 in words is "twenty billion, four hundred thirty-eight million, eight hundred fifty-five thousand, six hundred seventy-two".