72399399 has 16 divisors (see below), whose sum is σ = 102301920. Its totient is φ = 45463040.

The previous prime is 72399373. The next prime is 72399409. The reversal of 72399399 is 99399327.

It is a cyclic number.

It is not a de Polignac number, because 72399399 - 2²⁰ = 71350823 is a prime.

It is a super-2 number, since 2×72399399² = 10483345951122402, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72399319) 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, 6582 + ... + 13715.

It is an arithmetic number, because the mean of its divisors is an integer number (6393870).

Almost surely, 2^72399399 is an apocalyptic number.

72399399 is a deficient number, since it is larger than the sum of its proper divisors (29902521).

72399399 is a wasteful number, since it uses less digits than its factorization.

72399399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20370.

The product of its digits is 826686, while the sum is 51.

The square root of 72399399 is about 8508.7836381001. The cubic root of 72399399 is about 416.7845904802.

The spelling of 72399399 in words is "seventy-two million, three hundred ninety-nine thousand, three hundred ninety-nine".