21219850 has 12 divisors (see below), whose sum is σ = 39469014. Its totient is φ = 8487920.

The previous prime is 21219839. The next prime is 21219853. The reversal of 21219850 is 5891212.

It can be written as a sum of positive squares in 3 ways, for example, as 16410601 + 4809249 = 4051^2 + 2193^2 .

It is not an unprimeable number, because it can be changed into a prime (21219853) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 212149 + ... + 212248.

Almost surely, 2^21219850 is an apocalyptic number.

21219850 is a deficient number, since it is larger than the sum of its proper divisors (18249164).

21219850 is a wasteful number, since it uses less digits than its factorization.

21219850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424409 (or 424404 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 21219850 is about 4606.5008412026. The cubic root of 21219850 is about 276.8518542105.

The spelling of 21219850 in words is "twenty-one million, two hundred nineteen thousand, eight hundred fifty".