190381666 has 4 divisors (see below), whose sum is σ = 285572502. Its totient is φ = 95190832.

The previous prime is 190381663. The next prime is 190381699. The reversal of 190381666 is 666183091.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 158130625 + 32251041 = 12575^2 + 5679^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (190381663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 47595415 + ... + 47595418.

Almost surely, 2^190381666 is an apocalyptic number.

190381666 is a deficient number, since it is larger than the sum of its proper divisors (95190836).

190381666 is an equidigital number, since it uses as much as digits as its factorization.

190381666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95190835.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 190381666 is about 13797.8862873992. The cubic root of 190381666 is about 575.2743905268.

The spelling of 190381666 in words is "one hundred ninety million, three hundred eighty-one thousand, six hundred sixty-six".