661297716 has 24 divisors (see below), whose sum is σ = 1714475840. Its totient is φ = 220432536.

The previous prime is 661297711. The next prime is 661297757. The reversal of 661297716 is 617792166.

It is a happy number.

661297716 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661297711) 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, 3061456 + ... + 3061671.

Almost surely, 2^661297716 is an apocalyptic number.

It is an amenable number.

661297716 is an abundant number, since it is smaller than the sum of its proper divisors (1053178124).

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

661297716 is a wasteful number, since it uses less digits than its factorization.

661297716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6123140 (or 6123132 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 661297716 is about 25715.7095177248. The cubic root of 661297716 is about 871.2290358315.

The spelling of 661297716 in words is "six hundred sixty-one million, two hundred ninety-seven thousand, seven hundred sixteen".