215051220 has 96 divisors (see below), whose sum is σ = 675843840. Its totient is φ = 56764800.

The previous prime is 215051203. The next prime is 215051227. The reversal of 215051220 is 22150512.

215051220 is a `hidden beast` number, since 2 + 150 + 512 + 2 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 215051193 and 215051202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215051227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 52569 + ... + 56511.

It is an arithmetic number, because the mean of its divisors is an integer number (7040040).

Almost surely, 2^215051220 is an apocalyptic number.

215051220 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 215051220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (337921920).

215051220 is an abundant number, since it is smaller than the sum of its proper divisors (460792620).

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

215051220 is a wasteful number, since it uses less digits than its factorization.

215051220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4062 (or 4054 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 215051220 is about 14664.6247821075. The cubic root of 215051220 is about 599.1202105815.

The spelling of 215051220 in words is "two hundred fifteen million, fifty-one thousand, two hundred twenty".