1221354166 has 16 divisors (see below), whose sum is σ = 1887973920. Its totient is φ = 592208320.

The previous prime is 1221354163. The next prime is 1221354187. The reversal of 1221354166 is 6614531221.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221354161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30901 + ... + 58288.

It is an arithmetic number, because the mean of its divisors is an integer number (117998370).

Almost surely, 2^1221354166 is an apocalyptic number.

1221354166 is a deficient number, since it is larger than the sum of its proper divisors (666619754).

1221354166 is a wasteful number, since it uses less digits than its factorization.

1221354166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89399.

The product of its digits is 8640, while the sum is 31.

The square root of 1221354166 is about 34947.8778468736. The cubic root of 1221354166 is about 1068.9249300386.

Adding to 1221354166 its reverse (6614531221), we get a palindrome (7835885387).

The spelling of 1221354166 in words is "one billion, two hundred twenty-one million, three hundred fifty-four thousand, one hundred sixty-six".