21406514231 has 2 divisors, whose sum is σ = 21406514232. Its totient is φ = 21406514230.

The previous prime is 21406514221. The next prime is 21406514237. The reversal of 21406514231 is 13241560412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21406514231 is a prime.

It is a super-2 number, since 2×21406514231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21406514194 and 21406514203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21406514237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10703257115 + 10703257116.

It is an arithmetic number, because the mean of its divisors is an integer number (10703257116).

Almost surely, 2^21406514231 is an apocalyptic number.

21406514231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21406514231 is an equidigital number, since it uses as much as digits as its factorization.

21406514231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 29.

The spelling of 21406514231 in words is "twenty-one billion, four hundred six million, five hundred fourteen thousand, two hundred thirty-one".