20081801971 has 16 divisors (see below), whose sum is σ = 25088509440. Its totient is φ = 15615996480.

The previous prime is 20081801963. The next prime is 20081801981. The reversal of 20081801971 is 17910818002.

It is not a de Polignac number, because 20081801971 - 2³ = 20081801963 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20081801971.

It is not an unprimeable number, because it can be changed into a prime (20081801981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 230266 + ... + 305263.

It is an arithmetic number, because the mean of its divisors is an integer number (1568031840).

Almost surely, 2^20081801971 is an apocalyptic number.

20081801971 is a deficient number, since it is larger than the sum of its proper divisors (5006707469).

20081801971 is a wasteful number, since it uses less digits than its factorization.

20081801971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536034.

The product of its (nonzero) digits is 8064, while the sum is 37.

The spelling of 20081801971 in words is "twenty billion, eighty-one million, eight hundred one thousand, nine hundred seventy-one".