21835290 has 16 divisors (see below), whose sum is σ = 52404768. Its totient is φ = 5822736.

The previous prime is 21835267. The next prime is 21835309. The reversal of 21835290 is 9253812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 727843 = 21835290 / (2 + 1 + 8 + 3 + 5 + 2 + 9 + 0).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 363892 + ... + 363951.

It is an arithmetic number, because the mean of its divisors is an integer number (3275298).

Almost surely, 2^21835290 is an apocalyptic number.

21835290 is an abundant number, since it is smaller than the sum of its proper divisors (30569478).

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

21835290 is a wasteful number, since it uses less digits than its factorization.

21835290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727853.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 21835290 is about 4672.8246275674. The cubic root of 21835290 is about 279.5029020130.

The spelling of 21835290 in words is "twenty-one million, eight hundred thirty-five thousand, two hundred ninety".