221850000 has 360 divisors, whose sum is σ = 850023720. Its totient is φ = 53760000.

The previous prime is 221849987. The next prime is 221850037. The reversal of 221850000 is 58122.

It can be written as a sum of positive squares in 12 ways, for example, as 213276816 + 8573184 = 14604^2 + 2928^2 .

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 7649986 + ... + 7650014.

It is an arithmetic number, because the mean of its divisors is an integer number (2361177).

Almost surely, 2^221850000 is an apocalyptic number.

221850000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221850000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (425011860).

221850000 is an abundant number, since it is smaller than the sum of its proper divisors (628173720).

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

221850000 is a wasteful number, since it uses less digits than its factorization.

221850000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85 (or 56 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 221850000 is about 14894.6299047677. The cubic root of 221850000 is about 605.3684889482.

The spelling of 221850000 in words is "two hundred twenty-one million, eight hundred fifty thousand".