215305040 has 40 divisors (see below), whose sum is σ = 501296040. Its totient is φ = 85999616.

The previous prime is 215305037. The next prime is 215305061. The reversal of 215305040 is 40503512.

It can be written as a sum of positive squares in 4 ways, for example, as 10471696 + 204833344 = 3236^2 + 14312^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

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 7 ways as a sum of consecutive naturals, for example, 72872 + ... + 75768.

It is an arithmetic number, because the mean of its divisors is an integer number (12532401).

Almost surely, 2^215305040 is an apocalyptic number.

215305040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215305040 is an abundant number, since it is smaller than the sum of its proper divisors (285991000).

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

215305040 is a wasteful number, since it uses less digits than its factorization.

215305040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3839 (or 3833 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 215305040 is about 14673.2763894094. The cubic root of 215305040 is about 599.3558271683.

Adding to 215305040 its reverse (40503512), we get a palindrome (255808552).

The spelling of 215305040 in words is "two hundred fifteen million, three hundred five thousand, forty".