191012381 has 4 divisors (see below), whose sum is σ = 218299872. Its totient is φ = 163724892.

The previous prime is 191012369. The next prime is 191012413. The reversal of 191012381 is 183210191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 191012381 - 2¹⁰ = 191011357 is a prime.

It is a super-2 number, since 2×191012381² = 72971459390578322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 191012381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191012351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13643735 + ... + 13643748.

It is an arithmetic number, because the mean of its divisors is an integer number (54574968).

Almost surely, 2^191012381 is an apocalyptic number.

It is an amenable number.

191012381 is a deficient number, since it is larger than the sum of its proper divisors (27287491).

191012381 is an equidigital number, since it uses as much as digits as its factorization.

191012381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27287490.

The product of its (nonzero) digits is 432, while the sum is 26.

The square root of 191012381 is about 13820.7228826860. The cubic root of 191012381 is about 575.9089653665.

The spelling of 191012381 in words is "one hundred ninety-one million, twelve thousand, three hundred eighty-one".