659955778 has 4 divisors (see below), whose sum is σ = 989933670. Its totient is φ = 329977888.

The previous prime is 659955773. The next prime is 659955781. The reversal of 659955778 is 877559956.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 487217329 + 172738449 = 22073^2 + 13143^2 .

It is not an unprimeable number, because it can be changed into a prime (659955773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164988943 + ... + 164988946.

Almost surely, 2^659955778 is an apocalyptic number.

659955778 is a deficient number, since it is larger than the sum of its proper divisors (329977892).

659955778 is a wasteful number, since it uses less digits than its factorization.

659955778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329977891.

The product of its digits is 23814000, while the sum is 61.

The square root of 659955778 is about 25689.6044734052. The cubic root of 659955778 is about 870.6393230911.

The spelling of 659955778 in words is "six hundred fifty-nine million, nine hundred fifty-five thousand, seven hundred seventy-eight".