642431828 has 24 divisors (see below), whose sum is σ = 1141537320. Its totient is φ = 316293120.

The previous prime is 642431813. The next prime is 642431833. The reversal of 642431828 is 828134246.

642431828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 98049604 + 544382224 = 9902^2 + 23332^2 .

It is a junction number, because it is equal to n+sod(n) for n = 642431791 and 642431800.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 223118 + ... + 225978.

It is an arithmetic number, because the mean of its divisors is an integer number (47564055).

Almost surely, 2^642431828 is an apocalyptic number.

It is an amenable number.

642431828 is a deficient number, since it is larger than the sum of its proper divisors (499105492).

642431828 is a wasteful number, since it uses less digits than its factorization.

642431828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3707 (or 3705 counting only the distinct ones).

The product of its digits is 73728, while the sum is 38.

The square root of 642431828 is about 25346.2389320388. The cubic root of 642431828 is about 862.8639994934.

The spelling of 642431828 in words is "six hundred forty-two million, four hundred thirty-one thousand, eight hundred twenty-eight".