21042478867208 has 16 divisors (see below), whose sum is σ = 40372197827280. Its totient is φ = 10276559446608.

The previous prime is 21042478867199. The next prime is 21042478867229. The reversal of 21042478867208 is 80276887424012.

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, 30584998010 + ... + 30584998697.

It is an arithmetic number, because the mean of its divisors is an integer number (2523262364205).

Almost surely, 2^{21042478867208} is an apocalyptic number.

It is an amenable number.

21042478867208 is a deficient number, since it is larger than the sum of its proper divisors (19329718960072).

21042478867208 is a wasteful number, since it uses less digits than its factorization.

21042478867208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61169996756 (or 61169996752 counting only the distinct ones).

The product of its (nonzero) digits is 19267584, while the sum is 59.

The spelling of 21042478867208 in words is "twenty-one trillion, forty-two billion, four hundred seventy-eight million, eight hundred sixty-seven thousand, two hundred eight".