72980721 has 12 divisors (see below), whose sum is σ = 115000080. Its totient is φ = 44230680.

The previous prime is 72980717. The next prime is 72980731. The reversal of 72980721 is 12708927.

It is not a de Polignac number, because 72980721 - 2² = 72980717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72980701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 368491 + ... + 368688.

It is an arithmetic number, because the mean of its divisors is an integer number (9583340).

Almost surely, 2^72980721 is an apocalyptic number.

It is an amenable number.

72980721 is a deficient number, since it is larger than the sum of its proper divisors (42019359).

72980721 is a wasteful number, since it uses less digits than its factorization.

72980721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737196 (or 737193 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 72980721 is about 8542.8754526799. The cubic root of 72980721 is about 417.8971248553.

The spelling of 72980721 in words is "seventy-two million, nine hundred eighty thousand, seven hundred twenty-one".