20487389644 has 12 divisors (see below), whose sum is σ = 35854017304. Its totient is φ = 10243384704.

The previous prime is 20487389609. The next prime is 20487389651. The reversal of 20487389644 is 44698378402.

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, 137179 + ... + 244525.

Almost surely, 2^20487389644 is an apocalyptic number.

It is an amenable number.

20487389644 is a deficient number, since it is larger than the sum of its proper divisors (15366627660).

20487389644 is a wasteful number, since it uses less digits than its factorization.

20487389644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155064 (or 155062 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 55.

The spelling of 20487389644 in words is "twenty billion, four hundred eighty-seven million, three hundred eighty-nine thousand, six hundred forty-four".