642066965 has 24 divisors (see below), whose sum is σ = 854098560. Its totient is φ = 462395648.

The previous prime is 642066917. The next prime is 642066967. The reversal of 642066965 is 569660246.

It is not a de Polignac number, because 642066965 - 2¹⁶ = 642001429 is a prime.

It is a super-2 number, since 2×642066965² = 824499975088622450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642066967) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23576 + ... + 42894.

It is an arithmetic number, because the mean of its divisors is an integer number (35587440).

Almost surely, 2^642066965 is an apocalyptic number.

It is an amenable number.

642066965 is a deficient number, since it is larger than the sum of its proper divisors (212031595).

642066965 is a wasteful number, since it uses less digits than its factorization.

642066965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19381 (or 19364 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 44.

The square root of 642066965 is about 25339.0403330513. The cubic root of 642066965 is about 862.7006167791.

The spelling of 642066965 in words is "six hundred forty-two million, sixty-six thousand, nine hundred sixty-five".