221488657 has 16 divisors (see below), whose sum is σ = 246552768. Its totient is φ = 197668800.

The previous prime is 221488639. The next prime is 221488679. The reversal of 221488657 is 756884122.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 221488657 - 2¹¹ = 221486609 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221488607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54498 + ... + 58420.

It is an arithmetic number, because the mean of its divisors is an integer number (15409548).

Almost surely, 2^221488657 is an apocalyptic number.

It is an amenable number.

221488657 is a deficient number, since it is larger than the sum of its proper divisors (25064111).

221488657 is a wasteful number, since it uses less digits than its factorization.

221488657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080.

The product of its digits is 215040, while the sum is 43.

The square root of 221488657 is about 14882.4949857206. The cubic root of 221488657 is about 605.0396413248.

The spelling of 221488657 in words is "two hundred twenty-one million, four hundred eighty-eight thousand, six hundred fifty-seven".