215775252 has 252 divisors, whose sum is σ = 729354528. Its totient is φ = 54237600.

The previous prime is 215775223. The next prime is 215775277. The reversal of 215775252 is 252577512.

It is a tau number, because it is divible by the number of its divisors (252).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 6960477 + ... + 6960507.

It is an arithmetic number, because the mean of its divisors is an integer number (2894264).

Almost surely, 2^215775252 is an apocalyptic number.

215775252 is a gapful number since it is divisible by the number (22) 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 215775252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (364677264).

215775252 is an abundant number, since it is smaller than the sum of its proper divisors (513579276).

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

215775252 is a wasteful number, since it uses less digits than its factorization.

215775252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 54 counting only the distinct ones).

The product of its digits is 49000, while the sum is 36.

The square root of 215775252 is about 14689.2903844944. The cubic root of 215775252 is about 599.7918277822.

The spelling of 215775252 in words is "two hundred fifteen million, seven hundred seventy-five thousand, two hundred fifty-two".