661376617 has 16 divisors (see below), whose sum is σ = 740537280. Its totient is φ = 585446400.

The previous prime is 661376609. The next prime is 661376627. The reversal of 661376617 is 716673166.

It is not a de Polignac number, because 661376617 - 2³ = 661376609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661376627) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 302434 + ... + 304612.

It is an arithmetic number, because the mean of its divisors is an integer number (46283580).

Almost surely, 2^661376617 is an apocalyptic number.

It is an amenable number.

661376617 is a deficient number, since it is larger than the sum of its proper divisors (79160663).

661376617 is a wasteful number, since it uses less digits than its factorization.

661376617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2904.

The product of its digits is 190512, while the sum is 43.

The square root of 661376617 is about 25717.2435731359. The cubic root of 661376617 is about 871.2636839216.

The spelling of 661376617 in words is "six hundred sixty-one million, three hundred seventy-six thousand, six hundred seventeen".