21833442 has 16 divisors (see below), whose sum is σ = 48518880. Its totient is φ = 7277796.

The previous prime is 21833437. The next prime is 21833447. The reversal of 21833442 is 24433812.

21833442 is a `hidden beast` number, since 218 + 3 + 3 + 442 = 666.

It is an interprime number because it is at equal distance from previous prime (21833437) and next prime (21833447).

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 Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21833447) 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, 202108 + ... + 202215.

It is an arithmetic number, because the mean of its divisors is an integer number (3032430).

Almost surely, 2^21833442 is an apocalyptic number.

21833442 is an abundant number, since it is smaller than the sum of its proper divisors (26685438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21833442 is a wasteful number, since it uses less digits than its factorization.

21833442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404334 (or 404328 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 21833442 is about 4672.6268843125. The cubic root of 21833442 is about 279.4950166748.

It can be divided in two parts, 2183 and 3442, that added together give a square (5625 = 75²).

The spelling of 21833442 in words is "twenty-one million, eight hundred thirty-three thousand, four hundred forty-two".