2171662643 has 2 divisors, whose sum is σ = 2171662644. Its totient is φ = 2171662642.

The previous prime is 2171662613. The next prime is 2171662667. The reversal of 2171662643 is 3462661712.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2171662643 - 2⁸ = 2171662387 is a prime.

It is a super-2 number, since 2×2171662643² = 9432237270003490898, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2171662597 and 2171662606.

It is not a weakly prime, because it can be changed into another prime (2171662613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085831321 + 1085831322.

It is an arithmetic number, because the mean of its divisors is an integer number (1085831322).

Almost surely, 2^2171662643 is an apocalyptic number.

2171662643 is a deficient number, since it is larger than the sum of its proper divisors (1).

2171662643 is an equidigital number, since it uses as much as digits as its factorization.

2171662643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 38.

The square root of 2171662643 is about 46601.1013067288. The cubic root of 2171662643 is about 1294.9831580523.

The spelling of 2171662643 in words is "two billion, one hundred seventy-one million, six hundred sixty-two thousand, six hundred forty-three".