21456072 has 48 divisors (see below), whose sum is σ = 63395280. Its totient is φ = 6501600.

The previous prime is 21456067. The next prime is 21456077. The reversal of 21456072 is 27065412.

It is an interprime number because it is at equal distance from previous prime (21456067) and next prime (21456077).

It is not an unprimeable number, because it can be changed into a prime (21456077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12754 + ... + 14337.

It is an arithmetic number, because the mean of its divisors is an integer number (1320735).

Almost surely, 2^21456072 is an apocalyptic number.

21456072 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21456072 is an abundant number, since it is smaller than the sum of its proper divisors (41939208).

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

21456072 is a wasteful number, since it uses less digits than its factorization.

21456072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27114 (or 27107 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 21456072 is about 4632.0699476584. The cubic root of 21456072 is about 277.8753819255.

The spelling of 21456072 in words is "twenty-one million, four hundred fifty-six thousand, seventy-two".