1667670986 has 4 divisors (see below), whose sum is σ = 2501506482. Its totient is φ = 833835492.

The previous prime is 1667670883. The next prime is 1667670989. The reversal of 1667670986 is 6890767661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6890767661 = 4177 ⋅1649693.

It can be written as a sum of positive squares in only one way, i.e., 1442100625 + 225570361 = 37975^2 + 15019^2 .

It is a super-2 number, since 2×1667670986² = 5562253035092424392, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1667670989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 416917745 + ... + 416917748.

Almost surely, 2^1667670986 is an apocalyptic number.

1667670986 is a deficient number, since it is larger than the sum of its proper divisors (833835496).

1667670986 is an equidigital number, since it uses as much as digits as its factorization.

1667670986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833835495.

The product of its (nonzero) digits is 4572288, while the sum is 56.

The square root of 1667670986 is about 40837.1275434500. The cubic root of 1667670986 is about 1185.8692041244.

The spelling of 1667670986 in words is "one billion, six hundred sixty-seven million, six hundred seventy thousand, nine hundred eighty-six".