656420811 has 16 divisors (see below), whose sum is σ = 899817504. Its totient is φ = 425343744.

The previous prime is 656420719. The next prime is 656420819. The reversal of 656420811 is 118024656.

656420811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 656420811 - 2¹⁸ = 656158667 is a prime.

It is a super-2 number, since 2×656420811² = 861776562227795442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (656420819) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129945 + ... + 134901.

It is an arithmetic number, because the mean of its divisors is an integer number (56238594).

Almost surely, 2^656420811 is an apocalyptic number.

656420811 is a deficient number, since it is larger than the sum of its proper divisors (243396693).

656420811 is a wasteful number, since it uses less digits than its factorization.

656420811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6190.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 656420811 is about 25620.7105873354. The cubic root of 656420811 is about 869.0820506922.

It can be divided in two parts, 656420 and 811, that added together give a triangular number (657231 = T₁₁₄₆).

The spelling of 656420811 in words is "six hundred fifty-six million, four hundred twenty thousand, eight hundred eleven".