191664144 has 200 divisors, whose sum is σ = 652253888. Its totient is φ = 53187840.

The previous prime is 191664139. The next prime is 191664157. The reversal of 191664144 is 441466191.

191664144 is a `hidden beast` number, since 1 + 9 + 1 + 6 + 641 + 4 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 191664099 and 191664108.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 335379 + ... + 335949.

Almost surely, 2^191664144 is an apocalyptic number.

191664144 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191664144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326126944).

191664144 is an abundant number, since it is smaller than the sum of its proper divisors (460589744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191664144 is a wasteful number, since it uses less digits than its factorization.

191664144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635 (or 620 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 191664144 is about 13844.2819965501. The cubic root of 191664144 is about 576.5632511194.

The spelling of 191664144 in words is "one hundred ninety-one million, six hundred sixty-four thousand, one hundred forty-four".