642668895 has 48 divisors (see below), whose sum is σ = 1224916992. Its totient is φ = 309113280.

The previous prime is 642668881. The next prime is 642668899. The reversal of 642668895 is 598866246.

It is a happy number.

It is not a de Polignac number, because 642668895 - 2⁴ = 642668879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642668899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 57754 + ... + 67976.

It is an arithmetic number, because the mean of its divisors is an integer number (25519104).

Almost surely, 2^642668895 is an apocalyptic number.

642668895 is a deficient number, since it is larger than the sum of its proper divisors (582248097).

642668895 is a wasteful number, since it uses less digits than its factorization.

642668895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10372 (or 10369 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 54.

The square root of 642668895 is about 25350.9150722415. The cubic root of 642668895 is about 862.9701230355.

The spelling of 642668895 in words is "six hundred forty-two million, six hundred sixty-eight thousand, eight hundred ninety-five".