72320739 has 4 divisors (see below), whose sum is σ = 96427656. Its totient is φ = 48213824.

The previous prime is 72320723. The next prime is 72320753. The reversal of 72320739 is 93702327.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93702327 = 3 ⋅31234109.

It is a cyclic number.

It is not a de Polignac number, because 72320739 - 2⁴ = 72320723 is a prime.

It is a super-2 number, since 2×72320739² = 10460578579012242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72320789) 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, 12053454 + ... + 12053459.

It is an arithmetic number, because the mean of its divisors is an integer number (24106914).

Almost surely, 2^72320739 is an apocalyptic number.

72320739 is a deficient number, since it is larger than the sum of its proper divisors (24106917).

72320739 is a wasteful number, since it uses less digits than its factorization.

72320739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24106916.

The product of its (nonzero) digits is 15876, while the sum is 33.

The square root of 72320739 is about 8504.1600996218. The cubic root of 72320739 is about 416.6335940327.

The spelling of 72320739 in words is "seventy-two million, three hundred twenty thousand, seven hundred thirty-nine".