72093721 has 4 divisors (see below), whose sum is σ = 82392832. Its totient is φ = 61794612.

The previous prime is 72093713. The next prime is 72093737. The reversal of 72093721 is 12739027.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72093721 - 2³ = 72093713 is a prime.

It is a super-3 number, since 3×72093721³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72093701) 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, 5149545 + ... + 5149558.

It is an arithmetic number, because the mean of its divisors is an integer number (20598208).

Almost surely, 2^72093721 is an apocalyptic number.

It is an amenable number.

72093721 is a deficient number, since it is larger than the sum of its proper divisors (10299111).

72093721 is a wasteful number, since it uses less digits than its factorization.

72093721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10299110.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 72093721 is about 8490.8021411407. The cubic root of 72093721 is about 416.1971933239.

The spelling of 72093721 in words is "seventy-two million, ninety-three thousand, seven hundred twenty-one".