717957421 has 4 divisors (see below), whose sum is σ = 723438144. Its totient is φ = 712476700.

The previous prime is 717957403. The next prime is 717957463. The reversal of 717957421 is 124759717.

717957421 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, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 124759717 = 31 ⋅4024507.

It is a cyclic number.

It is not a de Polignac number, because 717957421 - 2²⁹ = 181086509 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 (717957521) 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, 2740165 + ... + 2740426.

It is an arithmetic number, because the mean of its divisors is an integer number (180859536).

Almost surely, 2^717957421 is an apocalyptic number.

It is an amenable number.

717957421 is a deficient number, since it is larger than the sum of its proper divisors (5480723).

717957421 is a wasteful number, since it uses less digits than its factorization.

717957421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5480722.

The product of its digits is 123480, while the sum is 43.

The square root of 717957421 is about 26794.7274850856. The cubic root of 717957421 is about 895.4325888566.

The spelling of 717957421 in words is "seven hundred seventeen million, nine hundred fifty-seven thousand, four hundred twenty-one".