72421644051 has 14 divisors (see below), whose sum is σ = 108582795260. Its totient is φ = 48281095548.

The previous prime is 72421644023. The next prime is 72421644073. The reversal of 72421644051 is 15044612427.

72421644051 is a `hidden beast` number, since 7 + 2 + 4 + 2 + 1 + 644 + 0 + 5 + 1 = 666.

It is not a de Polignac number, because 72421644051 - 2⁷ = 72421643923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72421643997 and 72421644015.

It is not an unprimeable number, because it can be changed into a prime (72421644011) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 49671181 + ... + 49672638.

Almost surely, 2^72421644051 is an apocalyptic number.

72421644051 is a deficient number, since it is larger than the sum of its proper divisors (36161151209).

72421644051 is an frugal number, since it uses more digits than its factorization.

72421644051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99343837 (or 99343822 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The spelling of 72421644051 in words is "seventy-two billion, four hundred twenty-one million, six hundred forty-four thousand, fifty-one".