21902000 has 80 divisors (see below), whose sum is σ = 54317952. Its totient is φ = 8537600.

The previous prime is 21901993. The next prime is 21902029. The reversal of 21902000 is 20912.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 93884 + ... + 94116.

Almost surely, 2^21902000 is an apocalyptic number.

21902000 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 21902000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27158976).

21902000 is an abundant number, since it is smaller than the sum of its proper divisors (32415952).

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

21902000 is a wasteful number, since it uses less digits than its factorization.

21902000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 21902000 is about 4679.9572647621. The cubic root of 21902000 is about 279.7872533600.

Adding to 21902000 its reverse (20912), we get a palindrome (21922912).

The spelling of 21902000 in words is "twenty-one million, nine hundred two thousand".