642996155 has 8 divisors (see below), whose sum is σ = 772137312. Its totient is φ = 514035648.

The previous prime is 642996139. The next prime is 642996197. The reversal of 642996155 is 551699246.

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

It is a cyclic number.

It is not a de Polignac number, because 642996155 - 2⁴ = 642996139 is a prime.

It is a Duffinian 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, 37202 + ... + 51671.

It is an arithmetic number, because the mean of its divisors is an integer number (96517164).

Almost surely, 2^642996155 is an apocalyptic number.

642996155 is a deficient number, since it is larger than the sum of its proper divisors (129141157).

642996155 is a wasteful number, since it uses less digits than its factorization.

642996155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90325.

The product of its digits is 583200, while the sum is 47.

The square root of 642996155 is about 25357.3688500996. The cubic root of 642996155 is about 863.1165787926.

The spelling of 642996155 in words is "six hundred forty-two million, nine hundred ninety-six thousand, one hundred fifty-five".