168991616 has 16 divisors (see below), whose sum is σ = 336663240. Its totient is φ = 84495744.

The previous prime is 168991607. The next prime is 168991619. The reversal of 168991616 is 616199861.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168991619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 659996 + ... + 660251.

Almost surely, 2^168991616 is an apocalyptic number.

168991616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

168991616 is a deficient number, since it is larger than the sum of its proper divisors (167671624).

168991616 is an equidigital number, since it uses as much as digits as its factorization.

168991616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1320261 (or 1320249 counting only the distinct ones).

The product of its digits is 139968, while the sum is 47.

The square root of 168991616 is about 12999.6775344622. The cubic root of 168991616 is about 552.8683385642.

The spelling of 168991616 in words is "one hundred sixty-eight million, nine hundred ninety-one thousand, six hundred sixteen".