1659213081 has 6 divisors (see below), whose sum is σ = 2396641130. Its totient is φ = 1106142048.

The previous prime is 1659213079. The next prime is 1659213137. The reversal of 1659213081 is 1803129561.

It can be written as a sum of positive squares in only one way, i.e., 894967056 + 764246025 = 29916^2 + 27645^2 .

It is not a de Polignac number, because 1659213081 - 2¹ = 1659213079 is a prime.

It is a super-2 number, since 2×1659213081² = 5505976096323025122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1659213011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92178496 + ... + 92178513.

Almost surely, 2^1659213081 is an apocalyptic number.

It is an amenable number.

1659213081 is a deficient number, since it is larger than the sum of its proper divisors (737428049).

1659213081 is a wasteful number, since it uses less digits than its factorization.

1659213081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184357015 (or 184357012 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 1659213081 is about 40733.4393465614. The cubic root of 1659213081 is about 1183.8610195802.

The spelling of 1659213081 in words is "one billion, six hundred fifty-nine million, two hundred thirteen thousand, eighty-one".