21859450 has 24 divisors (see below), whose sum is σ = 43051932. Its totient is φ = 8229120.

The previous prime is 21859447. The next prime is 21859451. The reversal of 21859450 is 5495812.

It can be written as a sum of positive squares in 6 ways, for example, as 12131289 + 9728161 = 3483^2 + 3119^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (21859451) 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, 12009 + ... + 13708.

Almost surely, 2^21859450 is an apocalyptic number.

21859450 is a deficient number, since it is larger than the sum of its proper divisors (21192482).

21859450 is a wasteful number, since it uses less digits than its factorization.

21859450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25746 (or 25741 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 21859450 is about 4675.4090730117. The cubic root of 21859450 is about 279.6059508095.

The spelling of 21859450 in words is "twenty-one million, eight hundred fifty-nine thousand, four hundred fifty".