20640052577 has 2 divisors, whose sum is σ = 20640052578. Its totient is φ = 20640052576.

The previous prime is 20640052561. The next prime is 20640052603. The reversal of 20640052577 is 77525004602.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10412977936 + 10227074641 = 102044^2 + 101129^2 .

It is a cyclic number.

It is not a de Polignac number, because 20640052577 - 2⁴ = 20640052561 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20640052577.

It is not a weakly prime, because it can be changed into another prime (20640012577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10320026288 + 10320026289.

It is an arithmetic number, because the mean of its divisors is an integer number (10320026289).

Almost surely, 2^20640052577 is an apocalyptic number.

It is an amenable number.

20640052577 is a deficient number, since it is larger than the sum of its proper divisors (1).

20640052577 is an equidigital number, since it uses as much as digits as its factorization.

20640052577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 117600, while the sum is 38.

The spelling of 20640052577 in words is "twenty billion, six hundred forty million, fifty-two thousand, five hundred seventy-seven".