656609451 has 32 divisors (see below), whose sum is σ = 927252480. Its totient is φ = 412483104.

The previous prime is 656609449. The next prime is 656609489. The reversal of 656609451 is 154906656.

It is not a de Polignac number, because 656609451 - 2¹ = 656609449 is a prime.

It is a super-2 number, since 2×656609451² = 862271942285042802, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (656609251) 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 31 ways as a sum of consecutive naturals, for example, 2138640 + ... + 2138946.

It is an arithmetic number, because the mean of its divisors is an integer number (28976640).

Almost surely, 2^656609451 is an apocalyptic number.

656609451 is a deficient number, since it is larger than the sum of its proper divisors (270643029).

656609451 is a wasteful number, since it uses less digits than its factorization.

656609451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695.

The product of its (nonzero) digits is 194400, while the sum is 42.

The square root of 656609451 is about 25624.3917196097. The cubic root of 656609451 is about 869.1652940087.

The spelling of 656609451 in words is "six hundred fifty-six million, six hundred nine thousand, four hundred fifty-one".