20431187620 has 24 divisors (see below), whose sum is σ = 44065103544. Its totient is φ = 7951597056.

The previous prime is 20431187617. The next prime is 20431187641. The reversal of 20431187620 is 2678113402.

It can be written as a sum of positive squares in 4 ways, for example, as 11360149056 + 9071038564 = 106584^2 + 95242^2 .

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, 13804117 + ... + 13805596.

It is an arithmetic number, because the mean of its divisors is an integer number (1836045981).

Almost surely, 2^20431187620 is an apocalyptic number.

20431187620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20431187620 is an abundant number, since it is smaller than the sum of its proper divisors (23633915924).

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

20431187620 is a wasteful number, since it uses less digits than its factorization.

20431187620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27609759 (or 27609757 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The spelling of 20431187620 in words is "twenty billion, four hundred thirty-one million, one hundred eighty-seven thousand, six hundred twenty".