642225665 has 16 divisors (see below), whose sum is σ = 810528768. Its totient is φ = 487561536.

The previous prime is 642225653. The next prime is 642225673. The reversal of 642225665 is 566522246.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642225665 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7382 + ... + 36591.

It is an arithmetic number, because the mean of its divisors is an integer number (50658048).

Almost surely, 2^642225665 is an apocalyptic number.

It is an amenable number.

642225665 is a deficient number, since it is larger than the sum of its proper divisors (168303103).

642225665 is a wasteful number, since it uses less digits than its factorization.

642225665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44128.

The product of its digits is 172800, while the sum is 38.

The square root of 642225665 is about 25342.1716709520. The cubic root of 642225665 is about 862.7716889657.

The spelling of 642225665 in words is "six hundred forty-two million, two hundred twenty-five thousand, six hundred sixty-five".