20408911231 has 2 divisors, whose sum is σ = 20408911232. Its totient is φ = 20408911230.

The previous prime is 20408911219. The next prime is 20408911283. The reversal of 20408911231 is 13211980402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20408911231 - 2¹⁷ = 20408780159 is a prime.

It is a super-2 number, since 2×20408911231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20408911193 and 20408911202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20408912231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10204455615 + 10204455616.

It is an arithmetic number, because the mean of its divisors is an integer number (10204455616).

Almost surely, 2^20408911231 is an apocalyptic number.

20408911231 is a deficient number, since it is larger than the sum of its proper divisors (1).

20408911231 is an equidigital number, since it uses as much as digits as its factorization.

20408911231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 31.

The spelling of 20408911231 in words is "twenty billion, four hundred eight million, nine hundred eleven thousand, two hundred thirty-one".