168687994 has 4 divisors (see below), whose sum is σ = 253031994. Its totient is φ = 84343996.

The previous prime is 168687971. The next prime is 168688027. The reversal of 168687994 is 499786861.

168687994 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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., 119617969 + 49070025 = 10937^2 + 7005^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42171997 + ... + 42172000.

Almost surely, 2^168687994 is an apocalyptic number.

168687994 is a deficient number, since it is larger than the sum of its proper divisors (84344000).

168687994 is an equidigital number, since it uses as much as digits as its factorization.

168687994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84343999.

The product of its digits is 5225472, while the sum is 58.

The square root of 168687994 is about 12987.9942254376. The cubic root of 168687994 is about 552.5370329319.

The spelling of 168687994 in words is "one hundred sixty-eight million, six hundred eighty-seven thousand, nine hundred ninety-four".