20992072987 has 2 divisors, whose sum is σ = 20992072988. Its totient is φ = 20992072986.

The previous prime is 20992072979. The next prime is 20992073009. The reversal of 20992072987 is 78927029902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20992072987 - 2³ = 20992072979 is a prime.

It is not a weakly prime, because it can be changed into another prime (20992052987) 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, 10496036493 + 10496036494.

It is an arithmetic number, because the mean of its divisors is an integer number (10496036494).

Almost surely, 2^20992072987 is an apocalyptic number.

20992072987 is a deficient number, since it is larger than the sum of its proper divisors (1).

20992072987 is an equidigital number, since it uses as much as digits as its factorization.

20992072987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2286144, while the sum is 55.

The spelling of 20992072987 in words is "twenty billion, nine hundred ninety-two million, seventy-two thousand, nine hundred eighty-seven".