21343812 has 36 divisors (see below), whose sum is σ = 57934800. Its totient is φ = 6098064.

The previous prime is 21343801. The next prime is 21343831. The reversal of 21343812 is 21834312.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17562 + ... + 18737.

It is an arithmetic number, because the mean of its divisors is an integer number (1609300).

Almost surely, 2^21343812 is an apocalyptic number.

It is an amenable number.

21343812 is an abundant number, since it is smaller than the sum of its proper divisors (36590988).

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

21343812 is a wasteful number, since it uses less digits than its factorization.

21343812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36320 (or 36311 counting only the distinct ones).

The product of its digits is 1152, while the sum is 24.

The square root of 21343812 is about 4619.9363631981. The cubic root of 21343812 is about 277.3899116929.

It can be divided in two parts, 21343 and 812, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 21343812 in words is "twenty-one million, three hundred forty-three thousand, eight hundred twelve".