21263892 has 48 divisors (see below), whose sum is σ = 55168512. Its totient is φ = 6330240.

The previous prime is 21263867. The next prime is 21263897. The reversal of 21263892 is 29836212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21263897) 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, 2638 + ... + 7034.

It is an arithmetic number, because the mean of its divisors is an integer number (1149344).

Almost surely, 2^21263892 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 21263892, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27584256).

21263892 is an abundant number, since it is smaller than the sum of its proper divisors (33904620).

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

21263892 is a wasteful number, since it uses less digits than its factorization.

21263892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4448 (or 4446 counting only the distinct ones).

The product of its digits is 10368, while the sum is 33.

The square root of 21263892 is about 4611.2787814228. The cubic root of 21263892 is about 277.0432580680.

It can be divided in two parts, 21263 and 892, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 21263892 in words is "twenty-one million, two hundred sixty-three thousand, eight hundred ninety-two".