21343516 has 6 divisors (see below), whose sum is σ = 37351160. Its totient is φ = 10671756.

The previous prime is 21343513. The next prime is 21343519. The reversal of 21343516 is 61534312.

It is an interprime number because it is at equal distance from previous prime (21343513) and next prime (21343519).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21343513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2667936 + ... + 2667943.

Almost surely, 2^21343516 is an apocalyptic number.

It is an amenable number.

21343516 is a deficient number, since it is larger than the sum of its proper divisors (16007644).

21343516 is a wasteful number, since it uses less digits than its factorization.

21343516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5335883 (or 5335881 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 21343516 is about 4619.9043280137. The cubic root of 21343516 is about 277.3886293885.

Adding to 21343516 its reverse (61534312), we get a palindrome (82877828).

The spelling of 21343516 in words is "twenty-one million, three hundred forty-three thousand, five hundred sixteen".