642521732 has 48 divisors (see below), whose sum is σ = 1210023360. Its totient is φ = 297464832.

The previous prime is 642521707. The next prime is 642521791. The reversal of 642521732 is 237125246.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1695119 + ... + 1695497.

It is an arithmetic number, because the mean of its divisors is an integer number (25208820).

Almost surely, 2^642521732 is an apocalyptic number.

It is an amenable number.

642521732 is a deficient number, since it is larger than the sum of its proper divisors (567501628).

642521732 is a wasteful number, since it uses less digits than its factorization.

642521732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740 (or 738 counting only the distinct ones).

The product of its digits is 20160, while the sum is 32.

The square root of 642521732 is about 25348.0123875621. The cubic root of 642521732 is about 862.9042482810.

Adding to 642521732 its reverse (237125246), we get a palindrome (879646978).

The spelling of 642521732 in words is "six hundred forty-two million, five hundred twenty-one thousand, seven hundred thirty-two".