642915757 has 8 divisors (see below), whose sum is σ = 731856960. Its totient is φ = 559056960.

The previous prime is 642915733. The next prime is 642915857. The reversal of 642915757 is 757519246.

642915757 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-642915757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642915257) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1270332 + ... + 1270837.

It is an arithmetic number, because the mean of its divisors is an integer number (91482120).

Almost surely, 2^642915757 is an apocalyptic number.

It is an amenable number.

642915757 is a deficient number, since it is larger than the sum of its proper divisors (88941203).

642915757 is a wasteful number, since it uses less digits than its factorization.

642915757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2541203.

The product of its digits is 529200, while the sum is 46.

The square root of 642915757 is about 25355.7835019942. The cubic root of 642915757 is about 863.0806035961.

The spelling of 642915757 in words is "six hundred forty-two million, nine hundred fifteen thousand, seven hundred fifty-seven".