642317765 has 8 divisors (see below), whose sum is σ = 770920440. Its totient is φ = 513761472.

The previous prime is 642317761. The next prime is 642317771. The reversal of 642317765 is 567713246.

It can be written as a sum of positive squares in 4 ways, for example, as 25391521 + 616926244 = 5039^2 + 24838^2 .

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 642317765 - 2² = 642317761 is a prime.

It is a super-2 number, since 2×642317765² = 825144222469190450, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642317761) 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, 38771 + ... + 52799.

It is an arithmetic number, because the mean of its divisors is an integer number (96365055).

Almost surely, 2^642317765 is an apocalyptic number.

It is an amenable number.

642317765 is a deficient number, since it is larger than the sum of its proper divisors (128602675).

642317765 is a wasteful number, since it uses less digits than its factorization.

642317765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23191.

The product of its digits is 211680, while the sum is 41.

The square root of 642317765 is about 25343.9887350038. The cubic root of 642317765 is about 862.8129296483.

The spelling of 642317765 in words is "six hundred forty-two million, three hundred seventeen thousand, seven hundred sixty-five".