21319131 has 8 divisors (see below), whose sum is σ = 28768320. Its totient is φ = 14041352.

The previous prime is 21319127. The next prime is 21319169. The reversal of 21319131 is 13191312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21319131 - 2² = 21319127 is a prime.

It is a super-2 number, since 2×21319131² = 909010693190322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21319098 and 21319107.

It is not an unprimeable number, because it can be changed into a prime (21319171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42561 + ... + 43058.

It is an arithmetic number, because the mean of its divisors is an integer number (3596040).

Almost surely, 2^21319131 is an apocalyptic number.

21319131 is a deficient number, since it is larger than the sum of its proper divisors (7449189).

21319131 is an equidigital number, since it uses as much as digits as its factorization.

21319131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85705.

The product of its digits is 162, while the sum is 21.

The square root of 21319131 is about 4617.2644498664. The cubic root of 21319131 is about 277.2829501528.

The spelling of 21319131 in words is "twenty-one million, three hundred nineteen thousand, one hundred thirty-one".