1668990698 has 16 divisors (see below), whose sum is σ = 2532314664. Its totient is φ = 824940480.

The previous prime is 1668990689. The next prime is 1668990721. The reversal of 1668990698 is 8960998661.

It can be written as a sum of positive squares in 4 ways, for example, as 1413534409 + 255456289 = 37597^2 + 15983^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1668990698.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48368 + ... + 75348.

Almost surely, 2^1668990698 is an apocalyptic number.

1668990698 is a deficient number, since it is larger than the sum of its proper divisors (863323966).

1668990698 is a wasteful number, since it uses less digits than its factorization.

1668990698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27337.

The product of its (nonzero) digits is 10077696, while the sum is 62.

The square root of 1668990698 is about 40853.2825853688. The cubic root of 1668990698 is about 1186.1819343114.

The spelling of 1668990698 in words is "one billion, six hundred sixty-eight million, nine hundred ninety thousand, six hundred ninety-eight".