190909091 has 2 divisors, whose sum is σ = 190909092. Its totient is φ = 190909090.

The previous prime is 190909057. The next prime is 190909097.

It is a happy number.

190909091 is nontrivially palindromic in base 10.

It is a strong prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 190909091 - 2⁶ = 190909027 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (190909097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95454545 + 95454546.

It is an arithmetic number, because the mean of its divisors is an integer number (95454546).

Almost surely, 2^190909091 is an apocalyptic number.

190909091 is a deficient number, since it is larger than the sum of its proper divisors (1).

190909091 is an equidigital number, since it uses as much as digits as its factorization.

190909091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 38.

The square root of 190909091 is about 13816.9855974449. The cubic root of 190909091 is about 575.8051390033.

The spelling of 190909091 in words is "one hundred ninety million, nine hundred nine thousand, ninety-one".