656021603 has 4 divisors (see below), whose sum is σ = 656110488. Its totient is φ = 655932720.

The previous prime is 656021599. The next prime is 656021621. The reversal of 656021603 is 306120656.

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

It is a cyclic number.

It is not a de Polignac number, because 656021603 - 2² = 656021599 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656021693) 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, 32258 + ... + 48503.

It is an arithmetic number, because the mean of its divisors is an integer number (164027622).

Almost surely, 2^656021603 is an apocalyptic number.

656021603 is a deficient number, since it is larger than the sum of its proper divisors (88885).

656021603 is an equidigital number, since it uses as much as digits as its factorization.

656021603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88884.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 656021603 is about 25612.9186739817. The cubic root of 656021603 is about 868.9058350402.

The spelling of 656021603 in words is "six hundred fifty-six million, twenty-one thousand, six hundred three".