21410340 has 96 divisors (see below), whose sum is σ = 72145920. Its totient is φ = 4634496.

The previous prime is 21410339. The next prime is 21410341. The reversal of 21410340 is 4301412.

It is an interprime number because it is at equal distance from previous prime (21410339) and next prime (21410341).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (21410341) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6639 + ... + 9321.

It is an arithmetic number, because the mean of its divisors is an integer number (751520).

Almost surely, 2^21410340 is an apocalyptic number.

21410340 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 21410340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36072960).

21410340 is an abundant number, since it is smaller than the sum of its proper divisors (50735580).

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

21410340 is a wasteful number, since it uses less digits than its factorization.

21410340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2721 (or 2719 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21410340 is about 4627.1308604793. The cubic root of 21410340 is about 277.6778180185.

Adding to 21410340 its reverse (4301412), we get a palindrome (25711752).

The spelling of 21410340 in words is "twenty-one million, four hundred ten thousand, three hundred forty".