642676613 has 4 divisors (see below), whose sum is σ = 650811840. Its totient is φ = 634541388.

The previous prime is 642676589. The next prime is 642676631. The reversal of 642676613 is 316676246.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642676613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642676693) 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, 4067495 + ... + 4067652.

It is an arithmetic number, because the mean of its divisors is an integer number (162702960).

Almost surely, 2^642676613 is an apocalyptic number.

It is an amenable number.

642676613 is a deficient number, since it is larger than the sum of its proper divisors (8135227).

642676613 is an equidigital number, since it uses as much as digits as its factorization.

642676613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8135226.

The product of its digits is 217728, while the sum is 41.

The square root of 642676613 is about 25351.0672950864. The cubic root of 642676613 is about 862.9735775757.

The spelling of 642676613 in words is "six hundred forty-two million, six hundred seventy-six thousand, six hundred thirteen".