21008292879281 has 8 divisors (see below), whose sum is σ = 21746710840680. Its totient is φ = 20270807855872.

The previous prime is 21008292879271. The next prime is 21008292879319. The reversal of 21008292879281 is 18297829280012.

It can be written as a sum of positive squares in 4 ways, for example, as 5662591344400 + 15345701534881 = 2379620^2 + 3917359^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21008292879281 is a prime.

It is a super-2 number, since 2×21008292879281² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21008292879281.

It is not an unprimeable number, because it can be changed into a prime (21008292879271) 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, 233188670 + ... + 233278743.

It is an arithmetic number, because the mean of its divisors is an integer number (2718338855085).

Almost surely, 2^{21008292879281} is an apocalyptic number.

It is an amenable number.

21008292879281 is a deficient number, since it is larger than the sum of its proper divisors (738417961399).

21008292879281 is a wasteful number, since it uses less digits than its factorization.

21008292879281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466468995.

The product of its (nonzero) digits is 4644864, while the sum is 59.

The spelling of 21008292879281 in words is "twenty-one trillion, eight billion, two hundred ninety-two million, eight hundred seventy-nine thousand, two hundred eighty-one".