72991017 has 32 divisors (see below), whose sum is σ = 120216960. Its totient is φ = 43392960.

The previous prime is 72991007. The next prime is 72991031. The reversal of 72991017 is 71019927.

It is not a de Polignac number, because 72991017 - 2⁴ = 72991001 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72991007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13423 + ... + 18059.

It is an arithmetic number, because the mean of its divisors is an integer number (3756780).

Almost surely, 2^72991017 is an apocalyptic number.

It is an amenable number.

72991017 is a deficient number, since it is larger than the sum of its proper divisors (47225943).

72991017 is a wasteful number, since it uses less digits than its factorization.

72991017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4710 (or 4704 counting only the distinct ones).

The product of its (nonzero) digits is 7938, while the sum is 36.

The square root of 72991017 is about 8543.4780388317. The cubic root of 72991017 is about 417.9167760107.

It can be divided in two parts, 729910 and 17, that added together give a palindrome (729927).

The spelling of 72991017 in words is "seventy-two million, nine hundred ninety-one thousand, seventeen".