221204151 has 24 divisors (see below), whose sum is σ = 365640704. Its totient is φ = 126236880.

The previous prime is 221204129. The next prime is 221204161. The reversal of 221204151 is 151402122.

It is not a de Polignac number, because 221204151 - 2⁹ = 221203639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221204161) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 59106 + ... + 62736.

Almost surely, 2^221204151 is an apocalyptic number.

221204151 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

221204151 is a deficient number, since it is larger than the sum of its proper divisors (144436553).

221204151 is a wasteful number, since it uses less digits than its factorization.

221204151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4611 (or 4608 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 221204151 is about 14872.9335035157. The cubic root of 221204151 is about 604.7804690379.

Adding to 221204151 its reverse (151402122), we get a palindrome (372606273).

The spelling of 221204151 in words is "two hundred twenty-one million, two hundred four thousand, one hundred fifty-one".