21759072 has 24 divisors (see below), whose sum is σ = 57117816. Its totient is φ = 7252992.

The previous prime is 21759053. The next prime is 21759091. The reversal of 21759072 is 27095712.

It is an interprime number because it is at equal distance from previous prime (21759053) and next prime (21759091).

It is a tau number, because it is divible by the number of its divisors (24).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113233 + ... + 113424.

It is an arithmetic number, because the mean of its divisors is an integer number (2379909).

Almost surely, 2^21759072 is an apocalyptic number.

It is an amenable number.

21759072 is an abundant number, since it is smaller than the sum of its proper divisors (35358744).

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

21759072 is a wasteful number, since it uses less digits than its factorization.

21759072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226670 (or 226662 counting only the distinct ones).

The product of its (nonzero) digits is 8820, while the sum is 33.

The square root of 21759072 is about 4664.6620456363. The cubic root of 21759072 is about 279.1773130664.

The spelling of 21759072 in words is "twenty-one million, seven hundred fifty-nine thousand, seventy-two".