657628394431 has 4 divisors (see below), whose sum is σ = 658978761232. Its totient is φ = 656278027632.

The previous prime is 657628394429. The next prime is 657628394443. The reversal of 657628394431 is 134493826756.

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

It is a cyclic number.

It is not a de Polignac number, because 657628394431 - 2¹ = 657628394429 is a prime.

It is a super-2 number, since 2×657628394431² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657628394461) 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, 675182670 + ... + 675183643.

It is an arithmetic number, because the mean of its divisors is an integer number (164744690308).

Almost surely, 2^657628394431 is an apocalyptic number.

657628394431 is a deficient number, since it is larger than the sum of its proper divisors (1350366801).

657628394431 is a wasteful number, since it uses less digits than its factorization.

657628394431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350366800.

The product of its digits is 26127360, while the sum is 58.

The spelling of 657628394431 in words is "six hundred fifty-seven billion, six hundred twenty-eight million, three hundred ninety-four thousand, four hundred thirty-one".