661446726 has 16 divisors (see below), whose sum is σ = 1353658944. Its totient is φ = 215354664.

The previous prime is 661446679. The next prime is 661446749. The reversal of 661446726 is 627644166.

It is a happy number.

It is a super-2 number, since 2×661446726² = 875023542672238152, 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 7 ways as a sum of consecutive naturals, for example, 1281616 + ... + 1282131.

It is an arithmetic number, because the mean of its divisors is an integer number (84603684).

Almost surely, 2^661446726 is an apocalyptic number.

661446726 is an abundant number, since it is smaller than the sum of its proper divisors (692212218).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661446726 is a wasteful number, since it uses less digits than its factorization.

661446726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2563795.

The product of its digits is 290304, while the sum is 42.

The square root of 661446726 is about 25718.6066107789. The cubic root of 661446726 is about 871.2944688358.

The spelling of 661446726 in words is "six hundred sixty-one million, four hundred forty-six thousand, seven hundred twenty-six".