221492565666 has 32 divisors (see below), whose sum is σ = 492377011200. Its totient is φ = 73805158800.

The previous prime is 221492565653. The next prime is 221492565733. The reversal of 221492565666 is 666565294122.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 556885 + ... + 867816.

It is an arithmetic number, because the mean of its divisors is an integer number (15386781600).

Almost surely, 2^221492565666 is an apocalyptic number.

221492565666 is an abundant number, since it is smaller than the sum of its proper divisors (270884445534).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221492565666 is a wasteful number, since it uses less digits than its factorization.

221492565666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1427591 (or 1427585 counting only the distinct ones).

The product of its digits is 9331200, while the sum is 54.

The spelling of 221492565666 in words is "two hundred twenty-one billion, four hundred ninety-two million, five hundred sixty-five thousand, six hundred sixty-six".