215042240 has 56 divisors (see below), whose sum is σ = 585228192. Its totient is φ = 73728000.

The previous prime is 215042237. The next prime is 215042273. The reversal of 215042240 is 42240512.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

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

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45761 + ... + 50240.

Almost surely, 2^215042240 is an apocalyptic number.

215042240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215042240 is an abundant number, since it is smaller than the sum of its proper divisors (370185952).

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

215042240 is an equidigital number, since it uses as much as digits as its factorization.

215042240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96025 (or 96015 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 215042240 is about 14664.3185999214. The cubic root of 215042240 is about 599.1118712126. Note that the first 3 decimals are identical.

Adding to 215042240 its reverse (42240512), we get a palindrome (257282752).

The spelling of 215042240 in words is "two hundred fifteen million, forty-two thousand, two hundred forty".