20315530777 has 4 divisors (see below), whose sum is σ = 20318253876. Its totient is φ = 20312807680.

The previous prime is 20315530771. The next prime is 20315530783. The reversal of 20315530777 is 77703551302.

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

It is an interprime number because it is at equal distance from previous prime (20315530771) and next prime (20315530783).

It can be written as a sum of positive squares in 2 ways, for example, as 17179082761 + 3136448016 = 131069^2 + 56004^2 .

It is a cyclic number.

It is not a de Polignac number, because 20315530777 - 2¹⁵ = 20315498009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20315530771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1350328 + ... + 1365289.

It is an arithmetic number, because the mean of its divisors is an integer number (5079563469).

Almost surely, 2^20315530777 is an apocalyptic number.

It is an amenable number.

20315530777 is a deficient number, since it is larger than the sum of its proper divisors (2723099).

20315530777 is an equidigital number, since it uses as much as digits as its factorization.

20315530777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2723098.

The product of its (nonzero) digits is 154350, while the sum is 40.

The spelling of 20315530777 in words is "twenty billion, three hundred fifteen million, five hundred thirty thousand, seven hundred seventy-seven".