20741971791 has 16 divisors (see below), whose sum is σ = 28989354240. Its totient is φ = 13176972480.

The previous prime is 20741971787. The next prime is 20741971867. The reversal of 20741971791 is 19717914702.

It is not a de Polignac number, because 20741971791 - 2² = 20741971787 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20741971791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20741971751) 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, 1955571 + ... + 1966148.

It is an arithmetic number, because the mean of its divisors is an integer number (1811834640).

Almost surely, 2^20741971791 is an apocalyptic number.

20741971791 is a deficient number, since it is larger than the sum of its proper divisors (8247382449).

20741971791 is a wasteful number, since it uses less digits than its factorization.

20741971791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3921806.

The product of its (nonzero) digits is 222264, while the sum is 48.

The spelling of 20741971791 in words is "twenty billion, seven hundred forty-one million, nine hundred seventy-one thousand, seven hundred ninety-one".