221449551 has 16 divisors (see below), whose sum is σ = 304846944. Its totient is φ = 142884864.

The previous prime is 221449537. The next prime is 221449567. The reversal of 221449551 is 155944122.

It is a de Polignac number, because none of the positive numbers 2^k-221449551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221449511) 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, 16255 + ... + 26591.

It is an arithmetic number, because the mean of its divisors is an integer number (19052934).

Almost surely, 2^221449551 is an apocalyptic number.

221449551 is a deficient number, since it is larger than the sum of its proper divisors (83397393).

221449551 is a wasteful number, since it uses less digits than its factorization.

221449551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10570.

The product of its digits is 14400, while the sum is 33.

The square root of 221449551 is about 14881.1811023185. The cubic root of 221449551 is about 605.0040306632.

The spelling of 221449551 in words is "two hundred twenty-one million, four hundred forty-nine thousand, five hundred fifty-one".