191889001 has 2 divisors, whose sum is σ = 191889002. Its totient is φ = 191889000.

The previous prime is 191888987. The next prime is 191889031. The reversal of 191889001 is 100988191.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 176491225 + 15397776 = 13285^2 + 3924^2 .

It is an emirp because it is prime and its reverse (100988191) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191889001 is a prime.

It is not a weakly prime, because it can be changed into another prime (191889031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95944500 + 95944501.

It is an arithmetic number, because the mean of its divisors is an integer number (95944501).

Almost surely, 2^191889001 is an apocalyptic number.

It is an amenable number.

191889001 is a deficient number, since it is larger than the sum of its proper divisors (1).

191889001 is an equidigital number, since it uses as much as digits as its factorization.

191889001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 37.

The square root of 191889001 is about 13852.4005500852. The cubic root of 191889001 is about 576.7886342896.

The spelling of 191889001 in words is "one hundred ninety-one million, eight hundred eighty-nine thousand, one".