215405340 has 24 divisors (see below), whose sum is σ = 603135120. Its totient is φ = 57441408.

The previous prime is 215405339. The next prime is 215405347. The reversal of 215405340 is 43504512.

It is a self number, because there is not a number n which added to its sum of digits gives 215405340.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215405347) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1794985 + ... + 1795104.

It is an arithmetic number, because the mean of its divisors is an integer number (25130630).

Almost surely, 2^215405340 is an apocalyptic number.

215405340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215405340 is an abundant number, since it is smaller than the sum of its proper divisors (387729780).

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

215405340 is a wasteful number, since it uses less digits than its factorization.

215405340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3590101 (or 3590099 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 215405340 is about 14676.6937693746. The cubic root of 215405340 is about 599.4488828270.

Adding to 215405340 its reverse (43504512), we get a palindrome (258909852).

The spelling of 215405340 in words is "two hundred fifteen million, four hundred five thousand, three hundred forty".