2171917639 has 2 divisors, whose sum is σ = 2171917640. Its totient is φ = 2171917638.

The previous prime is 2171917633. The next prime is 2171917651. The reversal of 2171917639 is 9367191712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2171917639 - 2²⁹ = 1635046727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2171917633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085958819 + 1085958820.

It is an arithmetic number, because the mean of its divisors is an integer number (1085958820).

Almost surely, 2^2171917639 is an apocalyptic number.

2171917639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2171917639 is an equidigital number, since it uses as much as digits as its factorization.

2171917639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142884, while the sum is 46.

The square root of 2171917639 is about 46603.8371703447. The cubic root of 2171917639 is about 1295.0338415847.

The spelling of 2171917639 in words is "two billion, one hundred seventy-one million, nine hundred seventeen thousand, six hundred thirty-nine".