21612346 has 16 divisors (see below), whose sum is σ = 37520640. Its totient is φ = 9144720.

The previous prime is 21612319. The next prime is 21612373. The reversal of 21612346 is 64321612.

It is an interprime number because it is at equal distance from previous prime (21612319) and next prime (21612373).

It is a self number, because there is not a number n which added to its sum of digits gives 21612346.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8665 + ... + 10876.

It is an arithmetic number, because the mean of its divisors is an integer number (2345040).

Almost surely, 2^21612346 is an apocalyptic number.

21612346 is a deficient number, since it is larger than the sum of its proper divisors (15908294).

21612346 is a wasteful number, since it uses less digits than its factorization.

21612346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19629.

The product of its digits is 1728, while the sum is 25.

The square root of 21612346 is about 4648.9080438314. The cubic root of 21612346 is about 278.5483801475.

Adding to 21612346 its reverse (64321612), we get a palindrome (85933958).

The spelling of 21612346 in words is "twenty-one million, six hundred twelve thousand, three hundred forty-six".