642938955 has 16 divisors (see below), whose sum is σ = 1029019680. Its totient is φ = 342795008.

The previous prime is 642938953. The next prime is 642938957. The reversal of 642938955 is 559839246.

It is an interprime number because it is at equal distance from previous prime (642938953) and next prime (642938957).

It is a cyclic number.

It is not a de Polignac number, because 642938955 - 2¹ = 642938953 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 642938898 and 642938907.

It is not an unprimeable number, because it can be changed into a prime (642938953) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81631 + ... + 89159.

It is an arithmetic number, because the mean of its divisors is an integer number (64313730).

Almost surely, 2^642938955 is an apocalyptic number.

642938955 is a deficient number, since it is larger than the sum of its proper divisors (386080725).

642938955 is a wasteful number, since it uses less digits than its factorization.

642938955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13230.

The product of its digits is 2332800, while the sum is 51.

The square root of 642938955 is about 25356.2409477430. The cubic root of 642938955 is about 863.0909841697.

The spelling of 642938955 in words is "six hundred forty-two million, nine hundred thirty-eight thousand, nine hundred fifty-five".