221949 has 24 divisors (see below), whose sum is σ = 396032. Its totient is φ = 116640.

The previous prime is 221941. The next prime is 221951. The reversal of 221949 is 949122.

It is not a de Polignac number, because 221949 - 2³ = 221941 is a prime.

It is a super-2 number, since 2×221949² = 98522717202, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

221949 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 684 + ... + 954.

2²²¹⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

221949 is a deficient number, since it is larger than the sum of its proper divisors (174083).

221949 is a wasteful number, since it uses less digits than its factorization.

221949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297 (or 294 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 221949 is about 471.1146357311. The cubic root of 221949 is about 60.5458523608.

The spelling of 221949 in words is "two hundred twenty-one thousand, nine hundred forty-nine".