191540 has 24 divisors (see below), whose sum is σ = 411432. Its totient is φ = 74880.

The previous prime is 191537. The next prime is 191551. The reversal of 191540 is 45191.

191540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1444 + 190096 = 38^2 + 436^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1142 + ... + 1298.

It is an arithmetic number, because the mean of its divisors is an integer number (17143).

2¹⁹¹⁵⁴⁰ is an apocalyptic number.

191540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191540 is an abundant number, since it is smaller than the sum of its proper divisors (219892).

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

191540 is a wasteful number, since it uses less digits than its factorization.

191540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 191540 is about 437.6528304490. The cubic root of 191540 is about 57.6438741085.

The spelling of 191540 in words is "one hundred ninety-one thousand, five hundred forty".