191786642 has 4 divisors (see below), whose sum is σ = 287679966. Its totient is φ = 95893320.

The previous prime is 191786633. The next prime is 191786659. The reversal of 191786642 is 246687191.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 246687191 = 2393 ⋅103087.

It can be written as a sum of positive squares in only one way, i.e., 185531641 + 6255001 = 13621^2 + 2501^2 .

It is a junction number, because it is equal to n+sod(n) for n = 191786593 and 191786602.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 47946659 + ... + 47946662.

Almost surely, 2^191786642 is an apocalyptic number.

191786642 is a deficient number, since it is larger than the sum of its proper divisors (95893324).

191786642 is an equidigital number, since it uses as much as digits as its factorization.

191786642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95893323.

The product of its digits is 145152, while the sum is 44.

The square root of 191786642 is about 13848.7054268621. The cubic root of 191786642 is about 576.6860576118.

The spelling of 191786642 in words is "one hundred ninety-one million, seven hundred eighty-six thousand, six hundred forty-two".