15894112666 has 4 divisors (see below), whose sum is σ = 23841169002. Its totient is φ = 7947056332.

The previous prime is 15894112657. The next prime is 15894112667. The reversal of 15894112666 is 66621149851.

It is a happy number.

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., 15804261225 + 89851441 = 125715^2 + 9479^2 .

It is a Smith number, since the sum of its digits (49) 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 (15894112667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3973528165 + ... + 3973528168.

Almost surely, 2^15894112666 is an apocalyptic number.

15894112666 is a deficient number, since it is larger than the sum of its proper divisors (7947056336).

15894112666 is an equidigital number, since it uses as much as digits as its factorization.

15894112666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7947056335.

The product of its digits is 622080, while the sum is 49.

The spelling of 15894112666 in words is "fifteen billion, eight hundred ninety-four million, one hundred twelve thousand, six hundred sixty-six".