221256633 has 32 divisors (see below), whose sum is σ = 329567616. Its totient is φ = 131148288.

The previous prime is 221256617. The next prime is 221256677. The reversal of 221256633 is 336652122.

221256633 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221256633 - 2⁴ = 221256617 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221256633.

It is not an unprimeable number, because it can be changed into a prime (221256613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 153685 + ... + 155117.

It is an arithmetic number, because the mean of its divisors is an integer number (10298988).

Almost surely, 2^221256633 is an apocalyptic number.

It is an amenable number.

221256633 is a deficient number, since it is larger than the sum of its proper divisors (108310983).

221256633 is a wasteful number, since it uses less digits than its factorization.

221256633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593.

The product of its digits is 12960, while the sum is 30.

The square root of 221256633 is about 14874.6977448283. The cubic root of 221256633 is about 604.8282945098.

The spelling of 221256633 in words is "two hundred twenty-one million, two hundred fifty-six thousand, six hundred thirty-three".