726493568661 has 24 divisors (see below), whose sum is σ = 1199368834560. Its totient is φ = 415112229216.

The previous prime is 726493568659. The next prime is 726493568683. The reversal of 726493568661 is 166865394627.

726493568661 is a `hidden beast` number, since 7 + 2 + 6 + 4 + 9 + 3 + 568 + 6 + 61 = 666.

It is not a de Polignac number, because 726493568661 - 2¹ = 726493568659 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726493568621) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 624700 + ... + 1357658.

It is an arithmetic number, because the mean of its divisors is an integer number (49973701440).

Almost surely, 2^726493568661 is an apocalyptic number.

It is an amenable number.

726493568661 is a deficient number, since it is larger than the sum of its proper divisors (472875265899).

726493568661 is a wasteful number, since it uses less digits than its factorization.

726493568661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 748705 (or 748702 counting only the distinct ones).

The product of its digits is 78382080, while the sum is 63.

The spelling of 726493568661 in words is "seven hundred twenty-six billion, four hundred ninety-three million, five hundred sixty-eight thousand, six hundred sixty-one".