20999192677 has 2 divisors, whose sum is σ = 20999192678. Its totient is φ = 20999192676.

The previous prime is 20999192633. The next prime is 20999192759. The reversal of 20999192677 is 77629199902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17926264321 + 3072928356 = 133889^2 + 55434^2 .

It is a cyclic number.

It is not a de Polignac number, because 20999192677 - 2¹⁹ = 20998668389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20999192077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10499596338 + 10499596339.

It is an arithmetic number, because the mean of its divisors is an integer number (10499596339).

Almost surely, 2^20999192677 is an apocalyptic number.

It is an amenable number.

20999192677 is a deficient number, since it is larger than the sum of its proper divisors (1).

20999192677 is an equidigital number, since it uses as much as digits as its factorization.

20999192677 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7715736, while the sum is 61.

The spelling of 20999192677 in words is "twenty billion, nine hundred ninety-nine million, one hundred ninety-two thousand, six hundred seventy-seven".