20471664431 has 2 divisors, whose sum is σ = 20471664432. Its totient is φ = 20471664430.

The previous prime is 20471664413. The next prime is 20471664467. The reversal of 20471664431 is 13446617402.

Together with previous prime (20471664413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20471664431 is a prime.

It is a super-2 number, since 2×20471664431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20471664481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10235832215 + 10235832216.

It is an arithmetic number, because the mean of its divisors is an integer number (10235832216).

Almost surely, 2^20471664431 is an apocalyptic number.

20471664431 is a deficient number, since it is larger than the sum of its proper divisors (1).

20471664431 is an equidigital number, since it uses as much as digits as its factorization.

20471664431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 38.

The spelling of 20471664431 in words is "twenty billion, four hundred seventy-one million, six hundred sixty-four thousand, four hundred thirty-one".