20431187621 has 16 divisors (see below), whose sum is σ = 22409931264. Its totient is φ = 18513503424.

The previous prime is 20431187617. The next prime is 20431187641. The reversal of 20431187621 is 12678113402.

It is not a de Polignac number, because 20431187621 - 2² = 20431187617 is a prime.

It is a super-3 number, since 3×20431187621³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20431187641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109100 + ... + 229706.

It is an arithmetic number, because the mean of its divisors is an integer number (1400620704).

Almost surely, 2^20431187621 is an apocalyptic number.

It is an amenable number.

20431187621 is a deficient number, since it is larger than the sum of its proper divisors (1978743643).

20431187621 is a wasteful number, since it uses less digits than its factorization.

20431187621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120860.

The product of its (nonzero) digits is 16128, while the sum is 35.

The spelling of 20431187621 in words is "twenty billion, four hundred thirty-one million, one hundred eighty-seven thousand, six hundred twenty-one".