21868750 has 24 divisors (see below), whose sum is σ = 41013000.
Its totient is φ = 8745000.
The previous prime is 21868723. The next prime is 21868751. The reversal of 21868750 is 5786812.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (21868751) by changing a digit.
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, 4501 + ... + 7999.
It is an arithmetic number, because the mean of its divisors is an integer number (1708875).
Almost surely, 221868750 is an apocalyptic number.
21868750 is the 2500-th nonagonal number.
21868750 is a deficient number, since it is larger than the sum of its proper divisors (19144250).
21868750 is an frugal number, since it uses more digits than its factorization.
21868750 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 3526 (or 3506 counting only the distinct ones).
The product of its (nonzero) digits is 26880, while the sum is 37.
The square root of 21868750 is about 4676.4035326306.
The cubic root of 21868750 is about 279.6455975322.
The spelling of 21868750 in words is "twenty-one million, eight hundred sixty-eight thousand, seven hundred fifty".