20800781331 has 16 divisors (see below), whose sum is σ = 31571147520. Its totient is φ = 12058423520.

The previous prime is 20800781327. The next prime is 20800781363. The reversal of 20800781331 is 13318700802.

It is not a de Polignac number, because 20800781331 - 2² = 20800781327 is a prime.

It is a super-2 number, since 2×20800781331² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 20800781292 and 20800781301.

It is not an unprimeable number, because it can be changed into a prime (20800781731) 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 15 ways as a sum of consecutive naturals, for example, 13701996 + ... + 13703513.

It is an arithmetic number, because the mean of its divisors is an integer number (1973196720).

Almost surely, 2^20800781331 is an apocalyptic number.

20800781331 is a deficient number, since it is larger than the sum of its proper divisors (10770366189).

20800781331 is a wasteful number, since it uses less digits than its factorization.

20800781331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27405546.

The product of its (nonzero) digits is 8064, while the sum is 33.

The spelling of 20800781331 in words is "twenty billion, eight hundred million, seven hundred eighty-one thousand, three hundred thirty-one".