21850026 has 32 divisors (see below), whose sum is σ = 48178368. Its totient is φ = 6551040.

The previous prime is 21849979. The next prime is 21850027. The reversal of 21850026 is 62005812.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21849978 and 21850005.

It is not an unprimeable number, because it can be changed into a prime (21850027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4696 + ... + 8108.

It is an arithmetic number, because the mean of its divisors is an integer number (1505574).

Almost surely, 2^21850026 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21850026, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24089184).

21850026 is an abundant number, since it is smaller than the sum of its proper divisors (26328342).

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

21850026 is a wasteful number, since it uses less digits than its factorization.

21850026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3526.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 21850026 is about 4674.4011381138. The cubic root of 21850026 is about 279.5657639911.

Adding to 21850026 its reverse (62005812), we get a palindrome (83855838).

The spelling of 21850026 in words is "twenty-one million, eight hundred fifty thousand, twenty-six".