21834890 has 48 divisors (see below), whose sum is σ = 49888224. Its totient is φ = 6804000.

The previous prime is 21834871. The next prime is 21834899. The reversal of 21834890 is 9843812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21834890.

It is not an unprimeable number, because it can be changed into a prime (21834899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3365 + ... + 7415.

It is an arithmetic number, because the mean of its divisors is an integer number (1039338).

Almost surely, 2^21834890 is an apocalyptic number.

21834890 is an abundant number, since it is smaller than the sum of its proper divisors (28053334).

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

21834890 is a wasteful number, since it uses less digits than its factorization.

21834890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4083 (or 4076 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 21834890 is about 4672.7818267067. The cubic root of 21834890 is about 279.5011952676.

The spelling of 21834890 in words is "twenty-one million, eight hundred thirty-four thousand, eight hundred ninety".