21433420 has 12 divisors (see below), whose sum is σ = 45010224. Its totient is φ = 8573360.

The previous prime is 21433417. The next prime is 21433421. The reversal of 21433420 is 2433412.

It is not an unprimeable number, because it can be changed into a prime (21433421) 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, 535816 + ... + 535855.

It is an arithmetic number, because the mean of its divisors is an integer number (3750852).

Almost surely, 2^21433420 is an apocalyptic number.

21433420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21433420 is an abundant number, since it is smaller than the sum of its proper divisors (23576804).

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

21433420 is a wasteful number, since it uses less digits than its factorization.

21433420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1071680 (or 1071678 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 21433420 is about 4629.6241748116. The cubic root of 21433420 is about 277.7775595850. Note that the first 3 decimals are identical.

Adding to 21433420 its reverse (2433412), we get a palindrome (23866832).

The spelling of 21433420 in words is "twenty-one million, four hundred thirty-three thousand, four hundred twenty".