21124768 has 24 divisors (see below), whose sum is σ = 47531232. Its totient is φ = 9053376.

The previous prime is 21124759. The next prime is 21124769. The reversal of 21124768 is 86742112.

It is not an unprimeable number, because it can be changed into a prime (21124769) 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, 46930 + ... + 47377.

It is an arithmetic number, because the mean of its divisors is an integer number (1980468).

Almost surely, 2^21124768 is an apocalyptic number.

21124768 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21124768 is an abundant number, since it is smaller than the sum of its proper divisors (26406464).

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

21124768 is an equidigital number, since it uses as much as digits as its factorization.

21124768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94324 (or 94316 counting only the distinct ones).

The product of its digits is 5376, while the sum is 31.

The square root of 21124768 is about 4596.1688393705. The cubic root of 21124768 is about 276.4377287073.

The spelling of 21124768 in words is "twenty-one million, one hundred twenty-four thousand, seven hundred sixty-eight".