20890149931 has 4 divisors (see below), whose sum is σ = 23874457072. Its totient is φ = 17905842792.

The previous prime is 20890149919. The next prime is 20890149979. The reversal of 20890149931 is 13994109802.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20890149931 - 2¹⁵ = 20890117163 is a prime.

It is a super-2 number, since 2×20890149931² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20890149911) 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 3 ways as a sum of consecutive naturals, for example, 1492153560 + ... + 1492153573.

It is an arithmetic number, because the mean of its divisors is an integer number (5968614268).

Almost surely, 2^20890149931 is an apocalyptic number.

20890149931 is a deficient number, since it is larger than the sum of its proper divisors (2984307141).

20890149931 is an equidigital number, since it uses as much as digits as its factorization.

20890149931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2984307140.

The product of its (nonzero) digits is 139968, while the sum is 46.

The spelling of 20890149931 in words is "twenty billion, eight hundred ninety million, one hundred forty-nine thousand, nine hundred thirty-one".