201215540 has 24 divisors (see below), whose sum is σ = 422954952. Its totient is φ = 80409600.

The previous prime is 201215527. The next prime is 201215549. The reversal of 201215540 is 45512102.

It can be written as a sum of positive squares in 4 ways, for example, as 12208036 + 189007504 = 3494^2 + 13748^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201215549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19832 + ... + 28208.

It is an arithmetic number, because the mean of its divisors is an integer number (17623123).

Almost surely, 2^201215540 is an apocalyptic number.

201215540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201215540 is an abundant number, since it is smaller than the sum of its proper divisors (221739412).

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

201215540 is a wasteful number, since it uses less digits than its factorization.

201215540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9587 (or 9585 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 201215540 is about 14185.0463517043. The cubic root of 201215540 is about 585.9859090292.

Adding to 201215540 its reverse (45512102), we get a palindrome (246727642).

The spelling of 201215540 in words is "two hundred one million, two hundred fifteen thousand, five hundred forty".