221220454 has 16 divisors (see below), whose sum is σ = 408407328. Its totient is φ = 87515712.

The previous prime is 221220443. The next prime is 221220457. The reversal of 221220454 is 454022122.

It is a super-2 number, since 2×221220454² = 97876978535932232, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221220457) 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, 607567 + ... + 607930.

It is an arithmetic number, because the mean of its divisors is an integer number (25525458).

Almost surely, 2^221220454 is an apocalyptic number.

221220454 is a deficient number, since it is larger than the sum of its proper divisors (187186874).

221220454 is a wasteful number, since it uses less digits than its factorization.

221220454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1215519.

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 221220454 is about 14873.4815695586. The cubic root of 221220454 is about 604.7953263446.

Adding to 221220454 its reverse (454022122), we get a palindrome (675242576).

The spelling of 221220454 in words is "two hundred twenty-one million, two hundred twenty thousand, four hundred fifty-four".