642688475 has 72 divisors (see below), whose sum is σ = 962802960. Its totient is φ = 422611200.

The previous prime is 642688469. The next prime is 642688513. The reversal of 642688475 is 574886246.

It is a happy number.

It is not a de Polignac number, because 642688475 - 2⁶ = 642688411 is a prime.

It is an unprimeable number.

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 71 ways as a sum of consecutive naturals, for example, 2320037 + ... + 2320313.

Almost surely, 2^642688475 is an apocalyptic number.

642688475 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

642688475 is a deficient number, since it is larger than the sum of its proper divisors (320114485).

642688475 is a wasteful number, since it uses less digits than its factorization.

642688475 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 365 counting only the distinct ones).

The product of its digits is 2580480, while the sum is 50.

The square root of 642688475 is about 25351.3012486539. The cubic root of 642688475 is about 862.9788868969.

The spelling of 642688475 in words is "six hundred forty-two million, six hundred eighty-eight thousand, four hundred seventy-five".