221786985 has 24 divisors (see below), whose sum is σ = 412796736. Its totient is φ = 101388000.

The previous prime is 221786977. The next prime is 221787001. The reversal of 221786985 is 589687122.

221786985 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 221786985 - 2³ = 221786977 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 150141 + ... + 151610.

It is an arithmetic number, because the mean of its divisors is an integer number (17199864).

Almost surely, 2^221786985 is an apocalyptic number.

It is an amenable number.

221786985 is a deficient number, since it is larger than the sum of its proper divisors (191009751).

221786985 is a wasteful number, since it uses less digits than its factorization.

221786985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 301773 (or 301766 counting only the distinct ones).

The product of its digits is 483840, while the sum is 48.

The square root of 221786985 is about 14892.5143948227. The cubic root of 221786985 is about 605.3111665716.

The spelling of 221786985 in words is "two hundred twenty-one million, seven hundred eighty-six thousand, nine hundred eighty-five".