194638665 has 16 divisors (see below), whose sum is σ = 335377728. Its totient is φ = 95822016.

The previous prime is 194638643. The next prime is 194638669. The reversal of 194638665 is 566836491.

It is not a de Polignac number, because 194638665 - 2²¹ = 192541513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (194638669) 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, 498879 + ... + 499268.

It is an arithmetic number, because the mean of its divisors is an integer number (20961108).

Almost surely, 2^194638665 is an apocalyptic number.

194638665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

194638665 is a deficient number, since it is larger than the sum of its proper divisors (140739063).

194638665 is a wasteful number, since it uses less digits than its factorization.

194638665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 998168.

The product of its digits is 933120, while the sum is 48.

The square root of 194638665 is about 13951.2961763415. The cubic root of 194638665 is about 579.5306001967.

The spelling of 194638665 in words is "one hundred ninety-four million, six hundred thirty-eight thousand, six hundred sixty-five".