20507320577 has 4 divisors (see below), whose sum is σ = 20509197060. Its totient is φ = 20505444096.

The previous prime is 20507320553. The next prime is 20507320579. The reversal of 20507320577 is 77502370502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5148923536 + 15358397041 = 71756^2 + 123929^2 .

It is a cyclic number.

It is not a de Polignac number, because 20507320577 - 2⁸ = 20507320321 is a prime.

It is a super-2 number, since 2×20507320577² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20507320577.

It is not an unprimeable number, because it can be changed into a prime (20507320579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 921752 + ... + 943737.

It is an arithmetic number, because the mean of its divisors is an integer number (5127299265).

Almost surely, 2^20507320577 is an apocalyptic number.

It is an amenable number.

20507320577 is a deficient number, since it is larger than the sum of its proper divisors (1876483).

20507320577 is a wasteful number, since it uses less digits than its factorization.

20507320577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1876482.

The product of its (nonzero) digits is 102900, while the sum is 38.

The spelling of 20507320577 in words is "twenty billion, five hundred seven million, three hundred twenty thousand, five hundred seventy-seven".