721720043 has 8 divisors (see below), whose sum is σ = 795127536. Its totient is φ = 649612000.

The previous prime is 721720033. The next prime is 721720093. The reversal of 721720043 is 340027127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721720043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 721719994 and 721720021.

It is not an unprimeable number, because it can be changed into a prime (721720033) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 323696 + ... + 325917.

It is an arithmetic number, because the mean of its divisors is an integer number (99390942).

Almost surely, 2^721720043 is an apocalyptic number.

721720043 is a deficient number, since it is larger than the sum of its proper divisors (73407493).

721720043 is a wasteful number, since it uses less digits than its factorization.

721720043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649725.

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 721720043 is about 26864.8477196503. The cubic root of 721720043 is about 896.9941047583.

The spelling of 721720043 in words is "seven hundred twenty-one million, seven hundred twenty thousand, forty-three".