72706717 has 4 divisors (see below), whose sum is σ = 72725436. Its totient is φ = 72688000.

The previous prime is 72706691. The next prime is 72706721. The reversal of 72706717 is 71760727.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 55517401 + 17189316 = 7451^2 + 4146^2 .

It is a cyclic number.

It is not a de Polignac number, because 72706717 - 2¹¹ = 72704669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72706727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1108 + ... + 12109.

It is an arithmetic number, because the mean of its divisors is an integer number (18181359).

Almost surely, 2^72706717 is an apocalyptic number.

It is an amenable number.

72706717 is a deficient number, since it is larger than the sum of its proper divisors (18719).

72706717 is a wasteful number, since it uses less digits than its factorization.

72706717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18718.

The product of its (nonzero) digits is 28812, while the sum is 37.

The square root of 72706717 is about 8526.8233827141. The cubic root of 72706717 is about 417.3734747534.

The spelling of 72706717 in words is "seventy-two million, seven hundred six thousand, seven hundred seventeen".