21718850 has 12 divisors (see below), whose sum is σ = 40397154. Its totient is φ = 8687520.

The previous prime is 21718849. The next prime is 21718871. The reversal of 21718850 is 5881712.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 13010449 + 8708401 = 3607^2 + 2951^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 217139 + ... + 217238.

Almost surely, 2^21718850 is an apocalyptic number.

21718850 is a deficient number, since it is larger than the sum of its proper divisors (18678304).

21718850 is a wasteful number, since it uses less digits than its factorization.

21718850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434389 (or 434384 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 21718850 is about 4660.3486994001. The cubic root of 21718850 is about 279.0051856883.

The spelling of 21718850 in words is "twenty-one million, seven hundred eighteen thousand, eight hundred fifty".