72504981 has 12 divisors (see below), whose sum is σ = 105657708. Its totient is φ = 47908224.

The previous prime is 72504979. The next prime is 72504997. The reversal of 72504981 is 18940527.

72504981 is a `hidden beast` number, since 72 + 504 + 9 + 81 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 40525956 + 31979025 = 6366^2 + 5655^2 .

It is not a de Polignac number, because 72504981 - 2¹ = 72504979 is a prime.

It is a super-2 number, since 2×72504981² = 10513944539620722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72504181) 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, 34630 + ... + 36663.

It is an arithmetic number, because the mean of its divisors is an integer number (8804809).

Almost surely, 2^72504981 is an apocalyptic number.

It is an amenable number.

72504981 is a deficient number, since it is larger than the sum of its proper divisors (33152727).

72504981 is a wasteful number, since it uses less digits than its factorization.

72504981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71412 (or 71409 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 72504981 is about 8514.9856723309. The cubic root of 72504981 is about 416.9870948165.

The spelling of 72504981 in words is "seventy-two million, five hundred four thousand, nine hundred eighty-one".