21834340 has 48 divisors (see below), whose sum is σ = 50871744. Its totient is φ = 7804800.

The previous prime is 21834331. The next prime is 21834349. The reversal of 21834340 is 4343812.

It is an interprime number because it is at equal distance from previous prime (21834331) and next prime (21834349).

It is not an unprimeable number, because it can be changed into a prime (21834349) by changing a digit.

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, 12607 + ... + 14233.

It is an arithmetic number, because the mean of its divisors is an integer number (1059828).

Almost surely, 2^21834340 is an apocalyptic number.

21834340 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 21834340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25435872).

21834340 is an abundant number, since it is smaller than the sum of its proper divisors (29037404).

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

21834340 is a wasteful number, since it uses less digits than its factorization.

21834340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1708 (or 1706 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 21834340 is about 4672.7229748831. The cubic root of 21834340 is about 279.4988484586.

The spelling of 21834340 in words is "twenty-one million, eight hundred thirty-four thousand, three hundred forty".