661444626 has 16 divisors (see below), whose sum is σ = 1380406464. Its totient is φ = 210895344.

The previous prime is 661444621. The next prime is 661444627. The reversal of 661444626 is 626444166.

It is not an unprimeable number, because it can be changed into a prime (661444621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2396401 + ... + 2396676.

It is an arithmetic number, because the mean of its divisors is an integer number (86275404).

Almost surely, 2^661444626 is an apocalyptic number.

661444626 is an abundant number, since it is smaller than the sum of its proper divisors (718961838).

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

661444626 is a wasteful number, since it uses less digits than its factorization.

661444626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4793105.

The product of its digits is 165888, while the sum is 39.

The square root of 661444626 is about 25718.5657842734. The cubic root of 661444626 is about 871.2935467559.

The spelling of 661444626 in words is "six hundred sixty-one million, four hundred forty-four thousand, six hundred twenty-six".