191321740 has 24 divisors (see below), whose sum is σ = 425410272. Its totient is φ = 72026880.

The previous prime is 191321707. The next prime is 191321747. The reversal of 191321740 is 47123191.

It is a junction number, because it is equal to n+sod(n) for n = 191321699 and 191321708.

It is not an unprimeable number, because it can be changed into a prime (191321747) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281016 + ... + 281695.

It is an arithmetic number, because the mean of its divisors is an integer number (17725428).

Almost surely, 2^191321740 is an apocalyptic number.

191321740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191321740 is an abundant number, since it is smaller than the sum of its proper divisors (234088532).

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

191321740 is a wasteful number, since it uses less digits than its factorization.

191321740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562737 (or 562735 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 191321740 is about 13831.9102079214. The cubic root of 191321740 is about 576.2197070481.

It can be divided in two parts, 1913 and 21740, that added together give a triangular number (23653 = T₂₁₇).

The spelling of 191321740 in words is "one hundred ninety-one million, three hundred twenty-one thousand, seven hundred forty".