721990563 has 8 divisors (see below), whose sum is σ = 1100176128. Its totient is φ = 412566024.

The previous prime is 721990531. The next prime is 721990567. The reversal of 721990563 is 365099127.

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

It is not a de Polignac number, because 721990563 - 2⁵ = 721990531 is a prime.

It is a super-2 number, since 2×721990563² = 1042540746122113938, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (721990567) 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, 17190231 + ... + 17190272.

It is an arithmetic number, because the mean of its divisors is an integer number (137522016).

Almost surely, 2^721990563 is an apocalyptic number.

721990563 is a deficient number, since it is larger than the sum of its proper divisors (378185565).

721990563 is a wasteful number, since it uses less digits than its factorization.

721990563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34380513.

The product of its (nonzero) digits is 102060, while the sum is 42.

The square root of 721990563 is about 26869.8820801283. The cubic root of 721990563 is about 897.1061632294.

The spelling of 721990563 in words is "seven hundred twenty-one million, nine hundred ninety thousand, five hundred sixty-three".