21255866281115 has 8 divisors (see below), whose sum is σ = 25675960329888. Its totient is φ = 16892079163200.

The previous prime is 21255866281061. The next prime is 21255866281127. The reversal of 21255866281115 is 51118266855212.

It is a happy number.

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

It is not a de Polignac number, because 21255866281115 - 2¹⁰ = 21255866280091 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14076731882 + ... + 14076733391.

It is an arithmetic number, because the mean of its divisors is an integer number (3209495041236).

Almost surely, 2^{21255866281115} is an apocalyptic number.

21255866281115 is a deficient number, since it is larger than the sum of its proper divisors (4420094048773).

21255866281115 is a wasteful number, since it uses less digits than its factorization.

21255866281115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28153465429.

The product of its digits is 2304000, while the sum is 53.

The spelling of 21255866281115 in words is "twenty-one trillion, two hundred fifty-five billion, eight hundred sixty-six million, two hundred eighty-one thousand, one hundred fifteen".