21995000 has 80 divisors (see below), whose sum is σ = 53139240. Its totient is φ = 8528000.

The previous prime is 21994993. The next prime is 21995033. The reversal of 21995000 is 59912.

It is a happy number.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 264959 + ... + 265041.

Almost surely, 2^21995000 is an apocalyptic number.

21995000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21995000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26569620).

21995000 is an abundant number, since it is smaller than the sum of its proper divisors (31144240).

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

21995000 is an equidigital number, since it uses as much as digits as its factorization.

21995000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162 (or 143 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 21995000 is about 4689.8827277449. The cubic root of 21995000 is about 280.1827038865.

The spelling of 21995000 in words is "twenty-one million, nine hundred ninety-five thousand".