20104475981 has 8 divisors (see below), whose sum is σ = 20318196600. Its totient is φ = 19891806208.

The previous prime is 20104475971. The next prime is 20104476011. The reversal of 20104475981 is 18957440102.

It can be written as a sum of positive squares in 4 ways, for example, as 11499130756 + 8605345225 = 107234^2 + 92765^2 .

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-20104475981 is a prime.

It is a super-2 number, since 2×20104475981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20104475921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 224216 + ... + 300801.

It is an arithmetic number, because the mean of its divisors is an integer number (2539774575).

Almost surely, 2^20104475981 is an apocalyptic number.

It is an amenable number.

20104475981 is a deficient number, since it is larger than the sum of its proper divisors (213720619).

20104475981 is a wasteful number, since it uses less digits than its factorization.

20104475981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525423.

The product of its (nonzero) digits is 80640, while the sum is 41.

The spelling of 20104475981 in words is "twenty billion, one hundred four million, four hundred seventy-five thousand, nine hundred eighty-one".