715689865621 has 16 divisors (see below), whose sum is σ = 735290342640. Its totient is φ = 696194542080.

The previous prime is 715689865619. The next prime is 715689865669. The reversal of 715689865621 is 126568986517.

It can be written as a sum of positive squares in 8 ways, for example, as 24114673521 + 691575192100 = 155289^2 + 831610^2 .

It is a cyclic number.

It is not a de Polignac number, because 715689865621 - 2¹ = 715689865619 is a prime.

It is a super-4 number, since 4×715689865621⁴ (a number of 49 digits) contains 4444 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 (715689865601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19606375 + ... + 19642843.

It is an arithmetic number, because the mean of its divisors is an integer number (45955646415).

Almost surely, 2^715689865621 is an apocalyptic number.

It is an amenable number.

715689865621 is a deficient number, since it is larger than the sum of its proper divisors (19600477019).

715689865621 is a wasteful number, since it uses less digits than its factorization.

715689865621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37896.

The product of its digits is 43545600, while the sum is 64.

The spelling of 715689865621 in words is "seven hundred fifteen billion, six hundred eighty-nine million, eight hundred sixty-five thousand, six hundred twenty-one".