721679983 has 4 divisors (see below), whose sum is σ = 759663160. Its totient is φ = 683696808.

The previous prime is 721679963. The next prime is 721680013. The reversal of 721679983 is 389976127.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 721679983 - 2²⁵ = 688125551 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 721679983.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721679963) 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, 18991560 + ... + 18991597.

It is an arithmetic number, because the mean of its divisors is an integer number (189915790).

Almost surely, 2^721679983 is an apocalyptic number.

721679983 is a deficient number, since it is larger than the sum of its proper divisors (37983177).

721679983 is a wasteful number, since it uses less digits than its factorization.

721679983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37983176.

The product of its digits is 1143072, while the sum is 52.

The square root of 721679983 is about 26864.1021253270. The cubic root of 721679983 is about 896.9775081804.

The spelling of 721679983 in words is "seven hundred twenty-one million, six hundred seventy-nine thousand, nine hundred eighty-three".