21364434131 has 4 divisors (see below), whose sum is σ = 21392217000. Its totient is φ = 21336651264.

The previous prime is 21364434109. The next prime is 21364434137. The reversal of 21364434131 is 13143446312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21364434131 is a prime.

It is a super-2 number, since 2×21364434131² (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 (21364434137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13890281 + ... + 13891818.

It is an arithmetic number, because the mean of its divisors is an integer number (5348054250).

Almost surely, 2^21364434131 is an apocalyptic number.

21364434131 is a deficient number, since it is larger than the sum of its proper divisors (27782869).

21364434131 is an equidigital number, since it uses as much as digits as its factorization.

21364434131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27782868.

The product of its digits is 20736, while the sum is 32.

The spelling of 21364434131 in words is "twenty-one billion, three hundred sixty-four million, four hundred thirty-four thousand, one hundred thirty-one".