21412040 has 32 divisors (see below), whose sum is σ = 51884280. Its totient is φ = 7905792.

The previous prime is 21412033. The next prime is 21412049. The reversal of 21412040 is 4021412.

It can be written as a sum of positive squares in 4 ways, for example, as 10666756 + 10745284 = 3266^2 + 3278^2 .

It is not an unprimeable number, because it can be changed into a prime (21412049) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 20069 + ... + 21108.

Almost surely, 2^21412040 is an apocalyptic number.

21412040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21412040 is an abundant number, since it is smaller than the sum of its proper divisors (30472240).

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

21412040 is a wasteful number, since it uses less digits than its factorization.

21412040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41201 (or 41197 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 21412040 is about 4627.3145559817. The cubic root of 21412040 is about 277.6851671124.

Adding to 21412040 its reverse (4021412), we get a palindrome (25433452).

The spelling of 21412040 in words is "twenty-one million, four hundred twelve thousand, forty".