190008991 has 2 divisors, whose sum is σ = 190008992. Its totient is φ = 190008990.

The previous prime is 190008971. The next prime is 190009031. The reversal of 190008991 is 199800091.

It is a weak prime.

It is an emirp because it is prime and its reverse (199800091) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 166800061 and 160008661.

It is a cyclic number.

It is not a de Polignac number, because 190008991 - 2¹⁵ = 189976223 is a prime.

It is a super-2 number, since 2×190008991² = 72206833321676162, 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 190008991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (190008971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95004495 + 95004496.

It is an arithmetic number, because the mean of its divisors is an integer number (95004496).

Almost surely, 2^190008991 is an apocalyptic number.

190008991 is a deficient number, since it is larger than the sum of its proper divisors (1).

190008991 is an equidigital number, since it uses as much as digits as its factorization.

190008991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 190008991 is about 13784.3748860803. The cubic root of 190008991 is about 574.8987758802.

The spelling of 190008991 in words is "one hundred ninety million, eight thousand, nine hundred ninety-one".