21424548 has 24 divisors (see below), whose sum is σ = 50192352. Its totient is φ = 7112704.

The previous prime is 21424547. The next prime is 21424549. The reversal of 21424548 is 84542412.

It is an interprime number because it is at equal distance from previous prime (21424547) and next prime (21424549).

It is a super-2 number, since 2×21424548² = 918022514008608, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21424547) 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, 390 + ... + 6557.

It is an arithmetic number, because the mean of its divisors is an integer number (2091348).

Almost surely, 2^21424548 is an apocalyptic number.

It is an amenable number.

21424548 is an abundant number, since it is smaller than the sum of its proper divisors (28767804).

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

21424548 is a wasteful number, since it uses less digits than its factorization.

21424548 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7211 (or 7209 counting only the distinct ones).

The product of its digits is 10240, while the sum is 30.

The square root of 21424548 is about 4628.6658985068. The cubic root of 21424548 is about 277.7392271953.

The spelling of 21424548 in words is "twenty-one million, four hundred twenty-four thousand, five hundred forty-eight".