83971021571 has 2 divisors, whose sum is σ = 83971021572. Its totient is φ = 83971021570.

The previous prime is 83971021523. The next prime is 83971021573. The reversal of 83971021571 is 17512017938.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 83971021571 - 2¹⁰ = 83971020547 is a prime.

It is a super-2 number, since 2×83971021571² (a number of 23 digits) contains 22 as substring.

Together with 83971021573, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (83971021573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41985510785 + 41985510786.

It is an arithmetic number, because the mean of its divisors is an integer number (41985510786).

Almost surely, 2^83971021571 is an apocalyptic number.

83971021571 is a deficient number, since it is larger than the sum of its proper divisors (1).

83971021571 is an equidigital number, since it uses as much as digits as its factorization.

83971021571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 44.

The spelling of 83971021571 in words is "eighty-three billion, nine hundred seventy-one million, twenty-one thousand, five hundred seventy-one".