664415726 has 24 divisors (see below), whose sum is σ = 1142675424. Its totient is φ = 288612480.

The previous prime is 664415707. The next prime is 664415737. The reversal of 664415726 is 627514466.

It is a happy number.

It is a super-2 number, since 2×664415726² = 882896513912214152, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52070 + ... + 63561.

It is an arithmetic number, because the mean of its divisors is an integer number (47611476).

Almost surely, 2^664415726 is an apocalyptic number.

664415726 is a deficient number, since it is larger than the sum of its proper divisors (478259698).

664415726 is a wasteful number, since it uses less digits than its factorization.

664415726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115676 (or 115663 counting only the distinct ones).

The product of its digits is 241920, while the sum is 41.

The square root of 664415726 is about 25776.2628400628. The cubic root of 664415726 is about 872.5961672092.

The spelling of 664415726 in words is "six hundred sixty-four million, four hundred fifteen thousand, seven hundred twenty-six".