642648655 has 8 divisors (see below), whose sum is σ = 841285584. Its totient is φ = 467380800.

The previous prime is 642648649. The next prime is 642648661. The reversal of 642648655 is 556846246.

It is an interprime number because it is at equal distance from previous prime (642648649) and next prime (642648661).

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

It is not a de Polignac number, because 642648655 - 2⁹ = 642648143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5842206 + ... + 5842315.

It is an arithmetic number, because the mean of its divisors is an integer number (105160698).

Almost surely, 2^642648655 is an apocalyptic number.

642648655 is a deficient number, since it is larger than the sum of its proper divisors (198636929).

642648655 is a wasteful number, since it uses less digits than its factorization.

642648655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11684537.

The product of its digits is 1382400, while the sum is 46.

The square root of 642648655 is about 25350.5158724630. The cubic root of 642648655 is about 862.9610635759.

The spelling of 642648655 in words is "six hundred forty-two million, six hundred forty-eight thousand, six hundred fifty-five".