642104357 has 4 divisors (see below), whose sum is σ = 642173100. Its totient is φ = 642035616.

The previous prime is 642104339. The next prime is 642104383. The reversal of 642104357 is 753401246.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 155725441 + 486378916 = 12479^2 + 22054^2 .

It is a cyclic number.

It is not a de Polignac number, because 642104357 - 2⁸ = 642104101 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 (642104857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17648 + ... + 39945.

It is an arithmetic number, because the mean of its divisors is an integer number (160543275).

Almost surely, 2^642104357 is an apocalyptic number.

It is an amenable number.

642104357 is a deficient number, since it is larger than the sum of its proper divisors (68743).

642104357 is a wasteful number, since it uses less digits than its factorization.

642104357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68742.

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 642104357 is about 25339.7781560928. The cubic root of 642104357 is about 862.7173634619.

The spelling of 642104357 in words is "six hundred forty-two million, one hundred four thousand, three hundred fifty-seven".