659559981 has 8 divisors (see below), whose sum is σ = 887481760. Its totient is φ = 435672432.

The previous prime is 659559961. The next prime is 659560001. The reversal of 659559981 is 189955956.

It is an interprime number because it is at equal distance from previous prime (659559961) and next prime (659560001).

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

It is not a de Polignac number, because 659559981 - 2¹⁰ = 659558957 is a prime.

It is a super-2 number, since 2×659559981² = 870038737073440722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (659559911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1008175 + ... + 1008828.

It is an arithmetic number, because the mean of its divisors is an integer number (110935220).

Almost surely, 2^659559981 is an apocalyptic number.

It is an amenable number.

659559981 is a deficient number, since it is larger than the sum of its proper divisors (227921779).

659559981 is a wasteful number, since it uses less digits than its factorization.

659559981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2017115.

The product of its digits is 4374000, while the sum is 57.

The square root of 659559981 is about 25681.8998713101. The cubic root of 659559981 is about 870.4652380209.

The spelling of 659559981 in words is "six hundred fifty-nine million, five hundred fifty-nine thousand, nine hundred eighty-one".