21315343 has 24 divisors (see below), whose sum is σ = 25814160. Its totient is φ = 17539200.

The previous prime is 21315341. The next prime is 21315353. The reversal of 21315343 is 34351312.

It is not a de Polignac number, because 21315343 - 2¹ = 21315341 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21315341) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 210993 + ... + 211093.

It is an arithmetic number, because the mean of its divisors is an integer number (1075590).

Almost surely, 2^21315343 is an apocalyptic number.

21315343 is a deficient number, since it is larger than the sum of its proper divisors (4498817).

21315343 is a wasteful number, since it uses less digits than its factorization.

21315343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 240 counting only the distinct ones).

The product of its digits is 1080, while the sum is 22.

The square root of 21315343 is about 4616.8542320502. The cubic root of 21315343 is about 277.2665265624.

Adding to 21315343 its reverse (34351312), we get a palindrome (55666655).

The spelling of 21315343 in words is "twenty-one million, three hundred fifteen thousand, three hundred forty-three".