642538320 has 80 divisors (see below), whose sum is σ = 2025673920. Its totient is φ = 168435712.

The previous prime is 642538313. The next prime is 642538349. The reversal of 642538320 is 23835246.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8529 + ... + 36848.

It is an arithmetic number, because the mean of its divisors is an integer number (25320924).

Almost surely, 2^642538320 is an apocalyptic number.

642538320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

642538320 is an abundant number, since it is smaller than the sum of its proper divisors (1383135600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642538320 is a wasteful number, since it uses less digits than its factorization.

642538320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45452 (or 45446 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 33.

The square root of 642538320 is about 25348.3395905925. The cubic root of 642538320 is about 862.9116740908.

The spelling of 642538320 in words is "six hundred forty-two million, five hundred thirty-eight thousand, three hundred twenty".