28081801213 has 8 divisors (see below), whose sum is σ = 28346867640. Its totient is φ = 27817943040.

The previous prime is 28081801193. The next prime is 28081801229. The reversal of 28081801213 is 31210818082.

It can be written as a sum of positive squares in 4 ways, for example, as 63393444 + 28018407769 = 7962^2 + 167387^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28081801213 - 2⁹ = 28081800701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28081801283) 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, 255328 + ... + 348361.

It is an arithmetic number, because the mean of its divisors is an integer number (3543358455).

Almost surely, 2^28081801213 is an apocalyptic number.

It is an amenable number.

28081801213 is a deficient number, since it is larger than the sum of its proper divisors (265066427).

28081801213 is a wasteful number, since it uses less digits than its factorization.

28081801213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 604127.

The product of its (nonzero) digits is 6144, while the sum is 34.

The spelling of 28081801213 in words is "twenty-eight billion, eighty-one million, eight hundred one thousand, two hundred thirteen".