721946491 has 24 divisors (see below), whose sum is σ = 857080224. Its totient is φ = 595338240.

The previous prime is 721946483. The next prime is 721946527. The reversal of 721946491 is 194649127.

It is not a de Polignac number, because 721946491 - 2³ = 721946483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721946411) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3664605 + ... + 3664801.

It is an arithmetic number, because the mean of its divisors is an integer number (35711676).

Almost surely, 2^721946491 is an apocalyptic number.

721946491 is a deficient number, since it is larger than the sum of its proper divisors (135133733).

721946491 is a wasteful number, since it uses less digits than its factorization.

721946491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471 (or 358 counting only the distinct ones).

The product of its digits is 108864, while the sum is 43.

The square root of 721946491 is about 26869.0619672515. The cubic root of 721946491 is about 897.0879090354.

The spelling of 721946491 in words is "seven hundred twenty-one million, nine hundred forty-six thousand, four hundred ninety-one".