20732391888 has 80 divisors (see below), whose sum is σ = 61071466176. Its totient is φ = 6003947520.

The previous prime is 20732391881. The next prime is 20732391893. The reversal of 20732391888 is 88819323702.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 20732391888.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20732391881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 966598 + ... + 987813.

Almost surely, 2^20732391888 is an apocalyptic number.

It is an amenable number.

20732391888 is an abundant number, since it is smaller than the sum of its proper divisors (40339074288).

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

20732391888 is a wasteful number, since it uses less digits than its factorization.

20732391888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1954452 (or 1954446 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 51.

The spelling of 20732391888 in words is "twenty billion, seven hundred thirty-two million, three hundred ninety-one thousand, eight hundred eighty-eight".