642642165 has 48 divisors (see below), whose sum is σ = 1220446656. Its totient is φ = 310233600.

The previous prime is 642642163. The next prime is 642642167. The reversal of 642642165 is 561246246.

642642165 is a `hidden beast` number, since 6 + 4 + 2 + 642 + 1 + 6 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (642642163) and next prime (642642167).

It is not a de Polignac number, because 642642165 - 2¹ = 642642163 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642642163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 116602 + ... + 121988.

It is an arithmetic number, because the mean of its divisors is an integer number (25425972).

Almost surely, 2^642642165 is an apocalyptic number.

It is an amenable number.

642642165 is a deficient number, since it is larger than the sum of its proper divisors (577804491).

642642165 is a wasteful number, since it uses less digits than its factorization.

642642165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5650 (or 5647 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 642642165 is about 25350.3878668552. The cubic root of 642642165 is about 862.9581586002.

The spelling of 642642165 in words is "six hundred forty-two million, six hundred forty-two thousand, one hundred sixty-five".