722628397 has 4 divisors (see below), whose sum is σ = 724345276. Its totient is φ = 720911520.

The previous prime is 722628391. The next prime is 722628407. The reversal of 722628397 is 793826227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 793826227 = 5693 ⋅139439.

It can be written as a sum of positive squares in 2 ways, for example, as 166564836 + 556063561 = 12906^2 + 23581^2 .

It is a cyclic number.

It is not a de Polignac number, because 722628397 - 2¹¹ = 722626349 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 (722628391) 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, 857808 + ... + 858649.

It is an arithmetic number, because the mean of its divisors is an integer number (181086319).

Almost surely, 2^722628397 is an apocalyptic number.

It is an amenable number.

722628397 is a deficient number, since it is larger than the sum of its proper divisors (1716879).

722628397 is a wasteful number, since it uses less digits than its factorization.

722628397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1716878.

The product of its digits is 508032, while the sum is 46.

The square root of 722628397 is about 26881.7483992392. The cubic root of 722628397 is about 897.3702647389.

The spelling of 722628397 in words is "seven hundred twenty-two million, six hundred twenty-eight thousand, three hundred ninety-seven".