21432412 has 12 divisors (see below), whose sum is σ = 39137616. Its totient is φ = 10250240.

The previous prime is 21432409. The next prime is 21432413. The reversal of 21432412 is 21423412.

It is a self number, because there is not a number n which added to its sum of digits gives 21432412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116389 + ... + 116572.

It is an arithmetic number, because the mean of its divisors is an integer number (3261468).

Almost surely, 2^21432412 is an apocalyptic number.

It is an amenable number.

21432412 is a deficient number, since it is larger than the sum of its proper divisors (17705204).

21432412 is a wasteful number, since it uses less digits than its factorization.

21432412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232988 (or 232986 counting only the distinct ones).

The product of its digits is 384, while the sum is 19.

The square root of 21432412 is about 4629.5153094034. The cubic root of 21432412 is about 277.7732049499.

Adding to 21432412 its reverse (21423412), we get a palindrome (42855824).

The spelling of 21432412 in words is "twenty-one million, four hundred thirty-two thousand, four hundred twelve".