656189009 has 8 divisors (see below), whose sum is σ = 750090048. Its totient is φ = 562327920.

The previous prime is 656188979. The next prime is 656189033. The reversal of 656189009 is 900981656.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 656189009 - 2²⁴ = 639411793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656189509) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46619 + ... + 59039.

It is an arithmetic number, because the mean of its divisors is an integer number (93761256).

Almost surely, 2^656189009 is an apocalyptic number.

It is an amenable number.

656189009 is a deficient number, since it is larger than the sum of its proper divisors (93901039).

656189009 is a wasteful number, since it uses less digits than its factorization.

656189009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19975.

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 656189009 is about 25616.1864648117. The cubic root of 656189009 is about 868.9797389474.

The spelling of 656189009 in words is "six hundred fifty-six million, one hundred eighty-nine thousand, nine".