72049721 has 4 divisors (see below), whose sum is σ = 72076944. Its totient is φ = 72022500.

The previous prime is 72049711. The next prime is 72049753. The reversal of 72049721 is 12794027.

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 a de Polignac number, because none of the positive numbers 2^k-72049721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72049711) 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, 9155 + ... + 15096.

It is an arithmetic number, because the mean of its divisors is an integer number (18019236).

Almost surely, 2^72049721 is an apocalyptic number.

It is an amenable number.

72049721 is a deficient number, since it is larger than the sum of its proper divisors (27223).

72049721 is a wasteful number, since it uses less digits than its factorization.

72049721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27222.

The product of its (nonzero) digits is 7056, while the sum is 32.

The square root of 72049721 is about 8488.2107066213. The cubic root of 72049721 is about 416.1125053972.

The spelling of 72049721 in words is "seventy-two million, forty-nine thousand, seven hundred twenty-one".