191057243 has 4 divisors (see below), whose sum is σ = 205753968. Its totient is φ = 176360520.

The previous prime is 191057227. The next prime is 191057291. The reversal of 191057243 is 342750191.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 191057243 - 2⁴ = 191057227 is a prime.

It is a super-2 number, since 2×191057243² = 73005740205522098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191057443) 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, 7348343 + ... + 7348368.

It is an arithmetic number, because the mean of its divisors is an integer number (51438492).

Almost surely, 2^191057243 is an apocalyptic number.

191057243 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

191057243 is a deficient number, since it is larger than the sum of its proper divisors (14696725).

191057243 is a wasteful number, since it uses less digits than its factorization.

191057243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14696724.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 191057243 is about 13822.3457849961. The cubic root of 191057243 is about 575.9540486668.

The spelling of 191057243 in words is "one hundred ninety-one million, fifty-seven thousand, two hundred forty-three".