21278028586828 has 48 divisors (see below), whose sum is σ = 42444686633440. Its totient is φ = 9252351360000.

The previous prime is 21278028586819. The next prime is 21278028586831. The reversal of 21278028586828 is 82868582087212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59314173 + ... + 59671828.

Almost surely, 2^{21278028586828} is an apocalyptic number.

It is an amenable number.

21278028586828 is a deficient number, since it is larger than the sum of its proper divisors (21166658046612).

21278028586828 is a wasteful number, since it uses less digits than its factorization.

21278028586828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118986218 (or 118986216 counting only the distinct ones).

The product of its (nonzero) digits is 110100480, while the sum is 67.

The spelling of 21278028586828 in words is "twenty-one trillion, two hundred seventy-eight billion, twenty-eight million, five hundred eighty-six thousand, eight hundred twenty-eight".