221081633 has 4 divisors (see below), whose sum is σ = 221376768. Its totient is φ = 220786500.

The previous prime is 221081621. The next prime is 221081657. The reversal of 221081633 is 336180122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221081633 - 2¹⁴ = 221065249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221081683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146441 + ... + 147942.

It is an arithmetic number, because the mean of its divisors is an integer number (55344192).

Almost surely, 2^221081633 is an apocalyptic number.

It is an amenable number.

221081633 is a deficient number, since it is larger than the sum of its proper divisors (295135).

221081633 is an equidigital number, since it uses as much as digits as its factorization.

221081633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295134.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 221081633 is about 14868.8141087311. The cubic root of 221081633 is about 604.6687921438.

The spelling of 221081633 in words is "two hundred twenty-one million, eighty-one thousand, six hundred thirty-three".