221413666 has 32 divisors (see below), whose sum is σ = 353808000. Its totient is φ = 103754112.

The previous prime is 221413657. The next prime is 221413667. The reversal of 221413666 is 666314122.

It is a super-2 number, since 2×221413666² = 98048022983119112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221413667) 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, 304195 + ... + 304921.

It is an arithmetic number, because the mean of its divisors is an integer number (11056500).

Almost surely, 2^221413666 is an apocalyptic number.

221413666 is a deficient number, since it is larger than the sum of its proper divisors (132394334).

221413666 is a wasteful number, since it uses less digits than its factorization.

221413666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906.

The product of its digits is 10368, while the sum is 31.

The square root of 221413666 is about 14879.9753360011. The cubic root of 221413666 is about 604.9713494162.

Adding to 221413666 its reverse (666314122), we get a palindrome (887727788).

The spelling of 221413666 in words is "two hundred twenty-one million, four hundred thirteen thousand, six hundred sixty-six".