821250221 has 8 divisors (see below), whose sum is σ = 896331744. Its totient is φ = 746239120.

The previous prime is 821250181. The next prime is 821250247. The reversal of 821250221 is 122052128.

821250221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-821250221 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821250821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8471 + ... + 41403.

It is an arithmetic number, because the mean of its divisors is an integer number (112041468).

Almost surely, 2^821250221 is an apocalyptic number.

It is an amenable number.

821250221 is a deficient number, since it is larger than the sum of its proper divisors (75081523).

821250221 is a wasteful number, since it uses less digits than its factorization.

821250221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35211.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 821250221 is about 28657.4636177035. The cubic root of 821250221 is about 936.4656096083.

The spelling of 821250221 in words is "eight hundred twenty-one million, two hundred fifty thousand, two hundred twenty-one".