21812346 has 12 divisors (see below), whose sum is σ = 47260122. Its totient is φ = 7270776.

The previous prime is 21812279. The next prime is 21812353. The reversal of 21812346 is 64321812.

It can be written as a sum of positive squares in only one way, i.e., 20930625 + 881721 = 4575^2 + 939^2 .

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 5 ways as a sum of consecutive naturals, for example, 605881 + ... + 605916.

Almost surely, 2^21812346 is an apocalyptic number.

21812346 is an abundant number, since it is smaller than the sum of its proper divisors (25447776).

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

21812346 is a wasteful number, since it uses less digits than its factorization.

21812346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1211805 (or 1211802 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21812346 is about 4670.3689361762. The cubic root of 21812346 is about 279.4049693838.

The spelling of 21812346 in words is "twenty-one million, eight hundred twelve thousand, three hundred forty-six".