2171969531 has 2 divisors, whose sum is σ = 2171969532. Its totient is φ = 2171969530.

The previous prime is 2171969483. The next prime is 2171969533. The reversal of 2171969531 is 1359691712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2171969531 - 2¹⁰ = 2171968507 is a prime.

It is a super-2 number, since 2×2171969531² = 9434903287184719922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 2171969533, 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 (2171969533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085984765 + 1085984766.

It is an arithmetic number, because the mean of its divisors is an integer number (1085984766).

Almost surely, 2^2171969531 is an apocalyptic number.

2171969531 is a deficient number, since it is larger than the sum of its proper divisors (1).

2171969531 is an equidigital number, since it uses as much as digits as its factorization.

2171969531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 102060, while the sum is 44.

The square root of 2171969531 is about 46604.3939022921. The cubic root of 2171969531 is about 1295.0441552601.

The spelling of 2171969531 in words is "two billion, one hundred seventy-one million, nine hundred sixty-nine thousand, five hundred thirty-one".