20981475892501 has 8 divisors (see below), whose sum is σ = 21177739759680. Its totient is φ = 20785215271968.

The previous prime is 20981475892451. The next prime is 20981475892513. The reversal of 20981475892501 is 10529857418902.

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 20981475892501 - 2⁹ = 20981475891989 is a prime.

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 20981475892501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20981475802501) 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, 13318945 + ... + 14810713.

It is an arithmetic number, because the mean of its divisors is an integer number (2647217469960).

Almost surely, 2^{20981475892501} is an apocalyptic number.

It is an amenable number.

20981475892501 is a deficient number, since it is larger than the sum of its proper divisors (196263867179).

20981475892501 is a wasteful number, since it uses less digits than its factorization.

20981475892501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623323.

The product of its (nonzero) digits is 14515200, while the sum is 61.

The spelling of 20981475892501 in words is "twenty trillion, nine hundred eighty-one billion, four hundred seventy-five million, eight hundred ninety-two thousand, five hundred one".