190405081 has 4 divisors (see below), whose sum is σ = 190627600. Its totient is φ = 190182564.

The previous prime is 190405073. The next prime is 190405093. The reversal of 190405081 is 180504091.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 180504091 = 29 ⋅6224279.

It is a cyclic number.

It is not a de Polignac number, because 190405081 - 2³ = 190405073 is a prime.

It is a super-2 number, since 2×190405081² = 72508189741233122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (190405021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109971 + ... + 111688.

It is an arithmetic number, because the mean of its divisors is an integer number (47656900).

Almost surely, 2^190405081 is an apocalyptic number.

It is an amenable number.

190405081 is a deficient number, since it is larger than the sum of its proper divisors (222519).

190405081 is an equidigital number, since it uses as much as digits as its factorization.

190405081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222518.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 190405081 is about 13798.7347608395. The cubic root of 190405081 is about 575.2979738511.

The spelling of 190405081 in words is "one hundred ninety million, four hundred five thousand, eighty-one".