642321792 has 192 divisors, whose sum is σ = 2205831600. Its totient is φ = 183472128.

The previous prime is 642321791. The next prime is 642321941. The reversal of 642321792 is 297123246.

642321792 is a `hidden beast` number, since 642 + 3 + 2 + 1 + 7 + 9 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642321791) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 167448 + ... + 171240.

Almost surely, 2^642321792 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642321792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1102915800).

642321792 is an abundant number, since it is smaller than the sum of its proper divisors (1563509808).

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

642321792 is a wasteful number, since it uses less digits than its factorization.

642321792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3830 (or 3805 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 642321792 is about 25344.0681817265. The cubic root of 642321792 is about 862.8147327747.

The spelling of 642321792 in words is "six hundred forty-two million, three hundred twenty-one thousand, seven hundred ninety-two".