191081400 has 96 divisors (see below), whose sum is σ = 596211840. Its totient is φ = 50623360.

The previous prime is 191081351. The next prime is 191081413. The reversal of 191081400 is 4180191.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99247 + ... + 101153.

It is an arithmetic number, because the mean of its divisors is an integer number (6210540).

Almost surely, 2^191081400 is an apocalyptic number.

191081400 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 191081400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (298105920).

191081400 is an abundant number, since it is smaller than the sum of its proper divisors (405130440).

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

191081400 is a wasteful number, since it uses less digits than its factorization.

191081400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2093 (or 2084 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 191081400 is about 13823.2195960275. The cubic root of 191081400 is about 575.9783219079.

The spelling of 191081400 in words is "one hundred ninety-one million, eighty-one thousand, four hundred".