221746789 has 8 divisors (see below), whose sum is σ = 250247520. Its totient is φ = 194636400.

The previous prime is 221746787. The next prime is 221746801. The reversal of 221746789 is 987647122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221746789 - 2¹ = 221746787 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221746783) 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, 347247 + ... + 347884.

It is an arithmetic number, because the mean of its divisors is an integer number (31280940).

Almost surely, 2^221746789 is an apocalyptic number.

221746789 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

221746789 is a deficient number, since it is larger than the sum of its proper divisors (28500731).

221746789 is a wasteful number, since it uses less digits than its factorization.

221746789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695171.

The product of its digits is 338688, while the sum is 46.

The square root of 221746789 is about 14891.1647966168. The cubic root of 221746789 is about 605.2745961094.

The spelling of 221746789 in words is "two hundred twenty-one million, seven hundred forty-six thousand, seven hundred eighty-nine".