2171661623 has 2 divisors, whose sum is σ = 2171661624. Its totient is φ = 2171661622.

The previous prime is 2171661559. The next prime is 2171661629. The reversal of 2171661623 is 3261661712.

2171661623 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2171661623 - 2⁶ = 2171661559 is a prime.

It is a super-2 number, since 2×2171661623² = 9432228409621988258, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2171661629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085830811 + 1085830812.

It is an arithmetic number, because the mean of its divisors is an integer number (1085830812).

Almost surely, 2^2171661623 is an apocalyptic number.

2171661623 is a deficient number, since it is larger than the sum of its proper divisors (1).

2171661623 is an equidigital number, since it uses as much as digits as its factorization.

2171661623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 35.

The square root of 2171661623 is about 46601.0903627801. The cubic root of 2171661623 is about 1294.9829553070.

The spelling of 2171661623 in words is "two billion, one hundred seventy-one million, six hundred sixty-one thousand, six hundred twenty-three".