642431621124 has 36 divisors (see below), whose sum is σ = 1623962283580. Its totient is φ = 214138874880.

The previous prime is 642431621101. The next prime is 642431621129. The reversal of 642431621124 is 421126134246.

642431621124 is a `hidden beast` number, since 6 + 4 + 2 + 4 + 3 + 1 + 621 + 1 + 24 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 397240272900 + 245191348224 = 630270^2 + 495168^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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 not an unprimeable number, because it can be changed into a prime (642431621129) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1561272 + ... + 1929360.

Almost surely, 2^642431621124 is an apocalyptic number.

It is an amenable number.

642431621124 is an abundant number, since it is smaller than the sum of its proper divisors (981530662456).

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

642431621124 is a wasteful number, since it uses less digits than its factorization.

642431621124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416580 (or 416575 counting only the distinct ones).

The product of its digits is 55296, while the sum is 36.

The spelling of 642431621124 in words is "six hundred forty-two billion, four hundred thirty-one million, six hundred twenty-one thousand, one hundred twenty-four".