20001971765971 has 8 divisors (see below), whose sum is σ = 21541655706480. Its totient is φ = 18462440786592.

The previous prime is 20001971765959. The next prime is 20001971765989. The reversal of 20001971765971 is 17956717910002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20001971765971 - 2²⁷ = 20001837548243 is a prime.

It is a super-3 number, since 3×20001971765971³ (a number of 41 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20001971765071) 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 7 ways as a sum of consecutive naturals, for example, 37968616 + ... + 38491813.

It is an arithmetic number, because the mean of its divisors is an integer number (2692706963310).

Almost surely, 2^{20001971765971} is an apocalyptic number.

20001971765971 is a deficient number, since it is larger than the sum of its proper divisors (1539683940509).

20001971765971 is a wasteful number, since it uses less digits than its factorization.

20001971765971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76480565.

The product of its (nonzero) digits is 1666980, while the sum is 55.

The spelling of 20001971765971 in words is "twenty trillion, one billion, nine hundred seventy-one million, seven hundred sixty-five thousand, nine hundred seventy-one".