642372665 has 12 divisors (see below), whose sum is σ = 847295652. Its totient is φ = 467179680.

The previous prime is 642372637. The next prime is 642372683. The reversal of 642372665 is 566273246.

It can be written as a sum of positive squares in 2 ways, for example, as 283989904 + 358382761 = 16852^2 + 18931^2 .

It is not a de Polignac number, because 642372665 - 2¹² = 642368569 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 530282 + ... + 531491.

It is an arithmetic number, because the mean of its divisors is an integer number (70607971).

Almost surely, 2^642372665 is an apocalyptic number.

It is an amenable number.

642372665 is a deficient number, since it is larger than the sum of its proper divisors (204922987).

642372665 is a wasteful number, since it uses less digits than its factorization.

642372665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1061800 (or 1061789 counting only the distinct ones).

The product of its digits is 362880, while the sum is 41.

The square root of 642372665 is about 25345.0718089336. The cubic root of 642372665 is about 862.8375109811.

The spelling of 642372665 in words is "six hundred forty-two million, three hundred seventy-two thousand, six hundred sixty-five".