642257227615 has 4 divisors (see below), whose sum is σ = 770708673144. Its totient is φ = 513805782088.

The previous prime is 642257227607. The next prime is 642257227663. The reversal of 642257227615 is 516722752246.

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 642257227615 - 2³ = 642257227607 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 3 ways as a sum of consecutive naturals, for example, 64225722757 + ... + 64225722766.

It is an arithmetic number, because the mean of its divisors is an integer number (192677168286).

Almost surely, 2^642257227615 is an apocalyptic number.

642257227615 is a deficient number, since it is larger than the sum of its proper divisors (128451445529).

642257227615 is a wasteful number, since it uses less digits than its factorization.

642257227615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128451445528.

The product of its digits is 2822400, while the sum is 49.

The spelling of 642257227615 in words is "six hundred forty-two billion, two hundred fifty-seven million, two hundred twenty-seven thousand, six hundred fifteen".