190666861 has 16 divisors (see below), whose sum is σ = 238146048. Its totient is φ = 148302000.

The previous prime is 190666841. The next prime is 190666867. The reversal of 190666861 is 168666091.

It is a happy number.

It is not a de Polignac number, because 190666861 - 2¹⁷ = 190535789 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (190666867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47586 + ... + 51436.

It is an arithmetic number, because the mean of its divisors is an integer number (14884128).

Almost surely, 2^190666861 is an apocalyptic number.

190666861 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

190666861 is a deficient number, since it is larger than the sum of its proper divisors (47479187).

190666861 is a wasteful number, since it uses less digits than its factorization.

190666861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4512.

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 190666861 is about 13808.2171550132. The cubic root of 190666861 is about 575.5615041744.

The spelling of 190666861 in words is "one hundred ninety million, six hundred sixty-six thousand, eight hundred sixty-one".