21242412 has 30 divisors (see below), whose sum is σ = 55532708. Its totient is φ = 7080696.

The previous prime is 21242393. The next prime is 21242443. The reversal of 21242412 is 21424212.

21242412 is a `hidden beast` number, since 212 + 42 + 412 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 32458 + ... + 33105.

Almost surely, 2^21242412 is an apocalyptic number.

It is an amenable number.

21242412 is an abundant number, since it is smaller than the sum of its proper divisors (34290296).

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

21242412 is a wasteful number, since it uses less digits than its factorization.

21242412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65579 (or 65568 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 21242412 is about 4608.9491210036. The cubic root of 21242412 is about 276.9499403427.

Adding to 21242412 its reverse (21424212), we get a palindrome (42666624).

It can be divided in two parts, 212 and 42412, that added together give a palindrome (42624).

The spelling of 21242412 in words is "twenty-one million, two hundred forty-two thousand, four hundred twelve".