20046656639 has 2 divisors, whose sum is σ = 20046656640. Its totient is φ = 20046656638.

The previous prime is 20046656621. The next prime is 20046656681. The reversal of 20046656639 is 93665664002.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20046656639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20046656593 and 20046656602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20046656689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10023328319 + 10023328320.

It is an arithmetic number, because the mean of its divisors is an integer number (10023328320).

Almost surely, 2^20046656639 is an apocalyptic number.

20046656639 is a deficient number, since it is larger than the sum of its proper divisors (1).

20046656639 is an equidigital number, since it uses as much as digits as its factorization.

20046656639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1399680, while the sum is 47.

The spelling of 20046656639 in words is "twenty billion, forty-six million, six hundred fifty-six thousand, six hundred thirty-nine".