191009664 has 224 divisors, whose sum is σ = 602024400. Its totient is φ = 60217344.

The previous prime is 191009653. The next prime is 191009699. The reversal of 191009664 is 466900191.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 2146132 + ... + 2146220.

Almost surely, 2^191009664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191009664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (301012200).

191009664 is an abundant number, since it is smaller than the sum of its proper divisors (411014736).

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

191009664 is an frugal number, since it uses more digits than its factorization.

191009664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 191009664 is about 13820.6245879121. The cubic root of 191009664 is about 575.9062347371.

The spelling of 191009664 in words is "one hundred ninety-one million, nine thousand, six hundred sixty-four".