191012543 has 2 divisors, whose sum is σ = 191012544. Its totient is φ = 191012542.

The previous prime is 191012519. The next prime is 191012551. The reversal of 191012543 is 345210191.

It is a strong prime.

It is an emirp because it is prime and its reverse (345210191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 191012543 - 2¹⁴ = 190996159 is a prime.

It is a Sophie Germain prime.

It is equal to p_10608434 and since 191012543 and 10608434 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191012593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95506271 + 95506272.

It is an arithmetic number, because the mean of its divisors is an integer number (95506272).

Almost surely, 2^191012543 is an apocalyptic number.

191012543 is a deficient number, since it is larger than the sum of its proper divisors (1).

191012543 is an equidigital number, since it uses as much as digits as its factorization.

191012543 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 191012543 is about 13820.7287434491. The cubic root of 191012543 is about 575.9091281783.

The spelling of 191012543 in words is "one hundred ninety-one million, twelve thousand, five hundred forty-three".