21424700 has 36 divisors (see below), whose sum is σ = 50720712. Its totient is φ = 7790400.

The previous prime is 21424699. The next prime is 21424759. The reversal of 21424700 is 742412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8639 + ... + 10838.

Almost surely, 2^21424700 is an apocalyptic number.

21424700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21424700 is an abundant number, since it is smaller than the sum of its proper divisors (29296012).

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

21424700 is a wasteful number, since it uses less digits than its factorization.

21424700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19502 (or 19495 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 20.

The square root of 21424700 is about 4628.6823178957. The cubic root of 21424700 is about 277.7398840160.

The spelling of 21424700 in words is "twenty-one million, four hundred twenty-four thousand, seven hundred".