21485850 has 24 divisors (see below), whose sum is σ = 53285280. Its totient is φ = 5729520.

The previous prime is 21485843. The next prime is 21485857. The reversal of 21485850 is 5858412.

It is an interprime number because it is at equal distance from previous prime (21485843) and next prime (21485857).

It is not an unprimeable number, because it can be changed into a prime (21485857) 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, 71470 + ... + 71769.

It is an arithmetic number, because the mean of its divisors is an integer number (2220220).

Almost surely, 2^21485850 is an apocalyptic number.

21485850 is an abundant number, since it is smaller than the sum of its proper divisors (31799430).

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

21485850 is a wasteful number, since it uses less digits than its factorization.

21485850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143254 (or 143249 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 33.

The square root of 21485850 is about 4635.2831628715. The cubic root of 21485850 is about 278.0038731065.

The spelling of 21485850 in words is "twenty-one million, four hundred eighty-five thousand, eight hundred fifty".