20013663154621 has 8 divisors (see below), whose sum is σ = 21192025136760. Its totient is φ = 18835422025728.

The previous prime is 20013663154603. The next prime is 20013663154627. The reversal of 20013663154621 is 12645136631002.

It can be written as a sum of positive squares in 4 ways, for example, as 307122122596 + 19706541032025 = 554186^2 + 4439205^2 .

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 20013663154621 - 2⁷ = 20013663154493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20013663154627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29872246 + ... + 30534871.

It is an arithmetic number, because the mean of its divisors is an integer number (2649003142095).

Almost surely, 2^{20013663154621} is an apocalyptic number.

It is an amenable number.

20013663154621 is a deficient number, since it is larger than the sum of its proper divisors (1178361982139).

20013663154621 is a wasteful number, since it uses less digits than its factorization.

20013663154621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60426623.

The product of its (nonzero) digits is 155520, while the sum is 40.

Adding to 20013663154621 its reverse (12645136631002), we get a palindrome (32658799785623).

The spelling of 20013663154621 in words is "twenty trillion, thirteen billion, six hundred sixty-three million, one hundred fifty-four thousand, six hundred twenty-one".