191238840 has 256 divisors, whose sum is σ = 702172800. Its totient is φ = 46006272.

The previous prime is 191238823. The next prime is 191238851. The reversal of 191238840 is 48832191.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is a junction number, because it is equal to n+sod(n) for n = 191238795 and 191238804.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 743992 + ... + 744248.

Almost surely, 2^191238840 is an apocalyptic number.

191238840 is a gapful number since it is divisible by the number (10) 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 191238840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (351086400).

191238840 is an abundant number, since it is smaller than the sum of its proper divisors (510933960).

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

191238840 is a wasteful number, since it uses less digits than its factorization.

191238840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343 (or 333 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 191238840 is about 13828.9131894014. The cubic root of 191238840 is about 576.1364694004.

The spelling of 191238840 in words is "one hundred ninety-one million, two hundred thirty-eight thousand, eight hundred forty".