21518090338 has 8 divisors (see below), whose sum is σ = 32327024832. Its totient is φ = 10742415396.

The previous prime is 21518090329. The next prime is 21518090371. The reversal of 21518090338 is 83309081512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21518090338.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8313270 + ... + 8315857.

It is an arithmetic number, because the mean of its divisors is an integer number (4040878104).

Almost surely, 2^21518090338 is an apocalyptic number.

21518090338 is a deficient number, since it is larger than the sum of its proper divisors (10808934494).

21518090338 is a wasteful number, since it uses less digits than its factorization.

21518090338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16629776.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 21518090338 in words is "twenty-one billion, five hundred eighteen million, ninety thousand, three hundred thirty-eight".