21371896 has 64 divisors (see below), whose sum is σ = 50964480. Its totient is φ = 8173440.

The previous prime is 21371893. The next prime is 21371929. The reversal of 21371896 is 69817312.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21371891) 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 15 ways as a sum of consecutive naturals, for example, 22095 + ... + 23041.

It is an arithmetic number, because the mean of its divisors is an integer number (796320).

Almost surely, 2^21371896 is an apocalyptic number.

21371896 is a gapful number since it is divisible by the number (26) 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 21371896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25482240).

21371896 is an abundant number, since it is smaller than the sum of its proper divisors (29592584).

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

21371896 is a wasteful number, since it uses less digits than its factorization.

21371896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004 (or 1000 counting only the distinct ones).

The product of its digits is 18144, while the sum is 37.

The square root of 21371896 is about 4622.9747998448. The cubic root of 21371896 is about 277.5115207727.

The spelling of 21371896 in words is "twenty-one million, three hundred seventy-one thousand, eight hundred ninety-six".