721674474376391 has 4 divisors (see below), whose sum is σ = 721674595566984. Its totient is φ = 721674353185800.

The previous prime is 721674474376321. The next prime is 721674474376411. The reversal of 721674474376391 is 193673474476127.

721674474376391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721674474376391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721674474376321) 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, 51174800 + ... + 63735461.

It is an arithmetic number, because the mean of its divisors is an integer number (180418648891746).

Almost surely, 2^{721674474376391} is an apocalyptic number.

721674474376391 is a deficient number, since it is larger than the sum of its proper divisors (121190593).

721674474376391 is a wasteful number, since it uses less digits than its factorization.

721674474376391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121190592.

The product of its digits is 896168448, while the sum is 71.

The spelling of 721674474376391 in words is "seven hundred twenty-one trillion, six hundred seventy-four billion, four hundred seventy-four million, three hundred seventy-six thousand, three hundred ninety-one".