21424488 has 32 divisors (see below), whose sum is σ = 56712960. Its totient is φ = 6721280.

The previous prime is 21424451. The next prime is 21424489. The reversal of 21424488 is 88442412.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21424489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25848 + ... + 26663.

It is an arithmetic number, because the mean of its divisors is an integer number (1772280).

Almost surely, 2^21424488 is an apocalyptic number.

It is an amenable number.

21424488 is an abundant number, since it is smaller than the sum of its proper divisors (35288472).

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

21424488 is a wasteful number, since it uses less digits than its factorization.

21424488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52537 (or 52533 counting only the distinct ones).

The product of its digits is 16384, while the sum is 33.

The square root of 21424488 is about 4628.6594171531. The cubic root of 21424488 is about 277.7389679231.

It can be divided in two parts, 21424 and 488, that added together give a palindrome (21912).

The spelling of 21424488 in words is "twenty-one million, four hundred twenty-four thousand, four hundred eighty-eight".