21278834750869 has 8 divisors (see below), whose sum is σ = 21334514876928. Its totient is φ = 21223165083120.

The previous prime is 21278834750863. The next prime is 21278834750917. The reversal of 21278834750869 is 96805743887212.

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 21278834750869 - 2³ = 21278834750861 is a prime.

It is a super-2 number, since 2×21278834750869² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21278834750798 and 21278834750807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21278834750861) 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, 1468344 + ... + 6686830.

It is an arithmetic number, because the mean of its divisors is an integer number (2666814359616).

It is a 2-persistent number, because it is pandigital, and so is 2⋅21278834750869 = 42557669501738, but 3⋅21278834750869 = 63836504252607 is not.

Almost surely, 2^{21278834750869} is an apocalyptic number.

It is an amenable number.

21278834750869 is a deficient number, since it is larger than the sum of its proper divisors (55680126059).

21278834750869 is a wasteful number, since it uses less digits than its factorization.

21278834750869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5229155.

The product of its (nonzero) digits is 325140480, while the sum is 70.

The spelling of 21278834750869 in words is "twenty-one trillion, two hundred seventy-eight billion, eight hundred thirty-four million, seven hundred fifty thousand, eight hundred sixty-nine".