215305991900 has 36 divisors (see below), whose sum is σ = 475132896840. Its totient is φ = 84662692800.

The previous prime is 215305991891. The next prime is 215305991911. The reversal of 215305991900 is 9199503512.

215305991900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×215305991900² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18240371 + ... + 18252170.

Almost surely, 2^215305991900 is an apocalyptic number.

215305991900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215305991900 is an abundant number, since it is smaller than the sum of its proper divisors (259826904940).

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

215305991900 is a wasteful number, since it uses less digits than its factorization.

215305991900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36492614 (or 36492607 counting only the distinct ones).

The product of its (nonzero) digits is 109350, while the sum is 44.

The spelling of 215305991900 in words is "two hundred fifteen billion, three hundred five million, nine hundred ninety-one thousand, nine hundred".