721919894 has 8 divisors (see below), whose sum is σ = 1083579120. Its totient is φ = 360726856.

The previous prime is 721919867. The next prime is 721919911. The reversal of 721919894 is 498919127.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112649 + ... + 118884.

It is an arithmetic number, because the mean of its divisors is an integer number (135447390).

Almost surely, 2^721919894 is an apocalyptic number.

721919894 is a deficient number, since it is larger than the sum of its proper divisors (361659226).

721919894 is a wasteful number, since it uses less digits than its factorization.

721919894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233094.

The product of its digits is 326592, while the sum is 50.

The square root of 721919894 is about 26868.5670254295. The cubic root of 721919894 is about 897.0768924571.

The spelling of 721919894 in words is "seven hundred twenty-one million, nine hundred nineteen thousand, eight hundred ninety-four".