642516365 has 8 divisors (see below), whose sum is σ = 779683320. Its totient is φ = 508237312.

The previous prime is 642516353. The next prime is 642516379. The reversal of 642516365 is 563615246.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6165289 + 636351076 = 2483^2 + 25226^2 .

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 642516365 - 2⁴ = 642516349 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 721484 + ... + 722373.

It is an arithmetic number, because the mean of its divisors is an integer number (97460415).

Almost surely, 2^642516365 is an apocalyptic number.

It is an amenable number.

642516365 is a deficient number, since it is larger than the sum of its proper divisors (137166955).

642516365 is a wasteful number, since it uses less digits than its factorization.

642516365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1443951.

The product of its digits is 129600, while the sum is 38.

The square root of 642516365 is about 25347.9065210522. The cubic root of 642516365 is about 862.9018456541.

The spelling of 642516365 in words is "six hundred forty-two million, five hundred sixteen thousand, three hundred sixty-five".