215218381388 has 12 divisors (see below), whose sum is σ = 376635928872. Its totient is φ = 107608116000.

The previous prime is 215218381387. The next prime is 215218381403. The reversal of 215218381388 is 883183812512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (215218381387) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 330263 + ... + 734513.

It is an arithmetic number, because the mean of its divisors is an integer number (31386327406).

Almost surely, 2^215218381388 is an apocalyptic number.

It is an amenable number.

215218381388 is a deficient number, since it is larger than the sum of its proper divisors (161417547484).

215218381388 is a wasteful number, since it uses less digits than its factorization.

215218381388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537352 (or 537350 counting only the distinct ones).

The product of its digits is 737280, while the sum is 50.

The spelling of 215218381388 in words is "two hundred fifteen billion, two hundred eighteen million, three hundred eighty-one thousand, three hundred eighty-eight".