72307720 has 16 divisors (see below), whose sum is σ = 162692460. Its totient is φ = 28923072.

The previous prime is 72307693. The next prime is 72307727. The reversal of 72307720 is 2770327.

It can be written as a sum of positive squares in 2 ways, for example, as 72284004 + 23716 = 8502^2 + 154^2 .

It is not an unprimeable number, because it can be changed into a prime (72307727) 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, 903807 + ... + 903886.

Almost surely, 2^72307720 is an apocalyptic number.

It is an amenable number.

72307720 is an abundant number, since it is smaller than the sum of its proper divisors (90384740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72307720 is a wasteful number, since it uses less digits than its factorization.

72307720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1807704 (or 1807700 counting only the distinct ones).

The product of its (nonzero) digits is 4116, while the sum is 28.

The square root of 72307720 is about 8503.3946162694. The cubic root of 72307720 is about 416.6085920838.

The spelling of 72307720 in words is "seventy-two million, three hundred seven thousand, seven hundred twenty".