72447931 has 16 divisors (see below), whose sum is σ = 82092960. Its totient is φ = 63521280.

The previous prime is 72447911. The next prime is 72447937. The reversal of 72447931 is 13974427.

It is a cyclic number.

It is not a de Polignac number, because 72447931 - 2¹³ = 72439739 is a prime.

It is a super-2 number, since 2×72447931² = 10497405412361522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72447937) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17865 + ... + 21541.

It is an arithmetic number, because the mean of its divisors is an integer number (5130810).

Almost surely, 2^72447931 is an apocalyptic number.

72447931 is a deficient number, since it is larger than the sum of its proper divisors (9645029).

72447931 is a wasteful number, since it uses less digits than its factorization.

72447931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3774.

The product of its digits is 42336, while the sum is 37.

The square root of 72447931 is about 8511.6350368187. The cubic root of 72447931 is about 416.8776983972.

The spelling of 72447931 in words is "seventy-two million, four hundred forty-seven thousand, nine hundred thirty-one".