79243721 has 4 divisors (see below), whose sum is σ = 79263744. Its totient is φ = 79223700.

The previous prime is 79243687. The next prime is 79243729. The reversal of 79243721 is 12734297.

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 79243721 - 2¹⁸ = 78981577 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (79243729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1865 + ... + 12726.

It is an arithmetic number, because the mean of its divisors is an integer number (19815936).

Almost surely, 2^79243721 is an apocalyptic number.

It is an amenable number.

79243721 is a deficient number, since it is larger than the sum of its proper divisors (20023).

79243721 is a wasteful number, since it uses less digits than its factorization.

79243721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20022.

The product of its digits is 21168, while the sum is 35.

The square root of 79243721 is about 8901.8942366218. The cubic root of 79243721 is about 429.5248419999.

The spelling of 79243721 in words is "seventy-nine million, two hundred forty-three thousand, seven hundred twenty-one".