191381616 has 50 divisors (see below), whose sum is σ = 553917672. Its totient is φ = 63793440.

The previous prime is 191381573. The next prime is 191381627. The reversal of 191381616 is 616183191.

It is a happy number.

191381616 is a `hidden beast` number, since 1 + 9 + 1 + 38 + 1 + 616 = 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 congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 72540 + ... + 75131.

Almost surely, 2^191381616 is an apocalyptic number.

191381616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

191381616 is an abundant number, since it is smaller than the sum of its proper divisors (362536056).

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

191381616 is a wasteful number, since it uses less digits than its factorization.

191381616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147691 (or 147676 counting only the distinct ones).

The product of its digits is 7776, while the sum is 36.

The square root of 191381616 is about 13834.0744540428. The cubic root of 191381616 is about 576.2798119663.

The spelling of 191381616 in words is "one hundred ninety-one million, three hundred eighty-one thousand, six hundred sixteen".