20681078731 has 16 divisors (see below), whose sum is σ = 21965598144. Its totient is φ = 19404227584.

The previous prime is 20681078707. The next prime is 20681078767. The reversal of 20681078731 is 13787018602.

It is not a de Polignac number, because 20681078731 - 2¹¹ = 20681076683 is a prime.

It is a super-2 number, since 2×20681078731² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20681070731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10481061 + ... + 10483033.

It is an arithmetic number, because the mean of its divisors is an integer number (1372849884).

Almost surely, 2^20681078731 is an apocalyptic number.

20681078731 is a deficient number, since it is larger than the sum of its proper divisors (1284519413).

20681078731 is a wasteful number, since it uses less digits than its factorization.

20681078731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3590.

The product of its (nonzero) digits is 112896, while the sum is 43.

The spelling of 20681078731 in words is "twenty billion, six hundred eighty-one million, seventy-eight thousand, seven hundred thirty-one".