190660861 has 2 divisors, whose sum is σ = 190660862. Its totient is φ = 190660860.

The previous prime is 190660853. The next prime is 190660901. The reversal of 190660861 is 168066091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 190605636 + 55225 = 13806^2 + 235^2 .

It is an emirp because it is prime and its reverse (168066091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 190660861 - 2³ = 190660853 is a prime.

It is a super-2 number, since 2×190660861² = 72703127834522642, 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 190660861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (190660061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95330430 + 95330431.

It is an arithmetic number, because the mean of its divisors is an integer number (95330431).

Almost surely, 2^190660861 is an apocalyptic number.

It is an amenable number.

190660861 is a deficient number, since it is larger than the sum of its proper divisors (1).

190660861 is an equidigital number, since it uses as much as digits as its factorization.

190660861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 190660861 is about 13807.9998913673. Note that the first 3 decimals coincide. The cubic root of 190660861 is about 575.5554667588. Note that the first 3 decimals are identical.

The spelling of 190660861 in words is "one hundred ninety million, six hundred sixty thousand, eight hundred sixty-one".