215531553340 has 24 divisors (see below), whose sum is σ = 452755280880. Its totient is φ = 86186141568.

The previous prime is 215531553301. The next prime is 215531553439. The reversal of 215531553340 is 43355135512.

It is a self number, because there is not a number n which added to its sum of digits gives 215531553340.

It is a congruent number.

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, 1588177 + ... + 1718536.

It is an arithmetic number, because the mean of its divisors is an integer number (18864803370).

Almost surely, 2^215531553340 is an apocalyptic number.

215531553340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215531553340 is an abundant number, since it is smaller than the sum of its proper divisors (237223727540).

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

215531553340 is a wasteful number, since it uses less digits than its factorization.

215531553340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3309981 (or 3309979 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 37.

Adding to 215531553340 its reverse (43355135512), we get a palindrome (258886688852).

The spelling of 215531553340 in words is "two hundred fifteen billion, five hundred thirty-one million, five hundred fifty-three thousand, three hundred forty".