661362917 has 12 divisors (see below), whose sum is σ = 703883460. Its totient is φ = 621282816.

The previous prime is 661362913. The next prime is 661362983. The reversal of 661362917 is 719263166.

It can be written as a sum of positive squares in 6 ways, for example, as 11826721 + 649536196 = 3439^2 + 25486^2 .

It is not a de Polignac number, because 661362917 - 2² = 661362913 is a prime.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661362913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 176459 + ... + 180167.

It is an arithmetic number, because the mean of its divisors is an integer number (58656955).

Almost surely, 2^661362917 is an apocalyptic number.

It is an amenable number.

661362917 is a deficient number, since it is larger than the sum of its proper divisors (42520543).

661362917 is a wasteful number, since it uses less digits than its factorization.

661362917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4360 (or 4343 counting only the distinct ones).

The product of its digits is 81648, while the sum is 41.

The square root of 661362917 is about 25716.9772135063. The cubic root of 661362917 is about 871.2576679872.

The spelling of 661362917 in words is "six hundred sixty-one million, three hundred sixty-two thousand, nine hundred seventeen".