21230892 has 72 divisors (see below), whose sum is σ = 57513456. Its totient is φ = 6580224.

The previous prime is 21230879. The next prime is 21230897. The reversal of 21230892 is 29803212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21230897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 69003 + ... + 69309.

It is an arithmetic number, because the mean of its divisors is an integer number (798798).

Almost surely, 2^21230892 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21230892, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28756728).

21230892 is an abundant number, since it is smaller than the sum of its proper divisors (36282564).

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

21230892 is a wasteful number, since it uses less digits than its factorization.

21230892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447 (or 442 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21230892 is about 4607.6992089328. The cubic root of 21230892 is about 276.8998669294.

It can be divided in two parts, 21230 and 892, that added together give a palindrome (22122).

The spelling of 21230892 in words is "twenty-one million, two hundred thirty thousand, eight hundred ninety-two".