21314340 has 120 divisors (see below), whose sum is σ = 68302080. Its totient is φ = 5562432.

The previous prime is 21314327. The next prime is 21314357. The reversal of 21314340 is 4341312.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 39 ways as a sum of consecutive naturals, for example, 95469 + ... + 95691.

It is an arithmetic number, because the mean of its divisors is an integer number (569184).

Almost surely, 2^21314340 is an apocalyptic number.

21314340 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 21314340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34151040).

21314340 is an abundant number, since it is smaller than the sum of its proper divisors (46987740).

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

21314340 is a wasteful number, since it uses less digits than its factorization.

21314340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303 (or 292 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 21314340 is about 4616.7456070267. The cubic root of 21314340 is about 277.2621775403.

Adding to 21314340 its reverse (4341312), we get a palindrome (25655652).

The spelling of 21314340 in words is "twenty-one million, three hundred fourteen thousand, three hundred forty".