20209496831 has 2 divisors, whose sum is σ = 20209496832. Its totient is φ = 20209496830.

The previous prime is 20209496807. The next prime is 20209496849. The reversal of 20209496831 is 13869490202.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20209496831 is a prime.

It is a super-2 number, since 2×20209496831² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20209496231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10104748415 + 10104748416.

It is an arithmetic number, because the mean of its divisors is an integer number (10104748416).

Almost surely, 2^20209496831 is an apocalyptic number.

20209496831 is a deficient number, since it is larger than the sum of its proper divisors (1).

20209496831 is an equidigital number, since it uses as much as digits as its factorization.

20209496831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 44.

The spelling of 20209496831 in words is "twenty billion, two hundred nine million, four hundred ninety-six thousand, eight hundred thirty-one".