190920181 has 2 divisors, whose sum is σ = 190920182. Its totient is φ = 190920180.

The previous prime is 190920173. The next prime is 190920187. The reversal of 190920181 is 181029091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 109307025 + 81613156 = 10455^2 + 9034^2 .

It is a cyclic number.

It is not a de Polignac number, because 190920181 - 2³ = 190920173 is a prime.

It is a super-2 number, since 2×190920181² = 72901031026145522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (190920187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95460090 + 95460091.

It is an arithmetic number, because the mean of its divisors is an integer number (95460091).

Almost surely, 2^190920181 is an apocalyptic number.

It is an amenable number.

190920181 is a deficient number, since it is larger than the sum of its proper divisors (1).

190920181 is an equidigital number, since it uses as much as digits as its factorization.

190920181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 190920181 is about 13817.3869092531. The cubic root of 190920181 is about 575.8162883856.

The spelling of 190920181 in words is "one hundred ninety million, nine hundred twenty thousand, one hundred eighty-one".