661896579 has 8 divisors (see below), whose sum is σ = 904054032. Its totient is φ = 430501760.

The previous prime is 661896563. The next prime is 661896583. The reversal of 661896579 is 975698166.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 661896579 - 2⁴ = 661896563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661896539) 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, 2690514 + ... + 2690759.

It is an arithmetic number, because the mean of its divisors is an integer number (113006754).

Almost surely, 2^661896579 is an apocalyptic number.

661896579 is a deficient number, since it is larger than the sum of its proper divisors (242157453).

661896579 is a wasteful number, since it uses less digits than its factorization.

661896579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5381317.

The product of its digits is 4898880, while the sum is 57.

The square root of 661896579 is about 25727.3507963801. The cubic root of 661896579 is about 871.4919478830.

The spelling of 661896579 in words is "six hundred sixty-one million, eight hundred ninety-six thousand, five hundred seventy-nine".