23991571 has 2 divisors, whose sum is σ = 23991572. Its totient is φ = 23991570.

The previous prime is 23991559. The next prime is 23991581. The reversal of 23991571 is 17519932.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 23991571 - 2¹¹ = 23989523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 23991571.

It is not a weakly prime, because it can be changed into another prime (23991581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11995785 + 11995786.

It is an arithmetic number, because the mean of its divisors is an integer number (11995786).

Almost surely, 2^23991571 is an apocalyptic number.

23991571 is a deficient number, since it is larger than the sum of its proper divisors (1).

23991571 is an equidigital number, since it uses as much as digits as its factorization.

23991571 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17010, while the sum is 37.

The square root of 23991571 is about 4898.1191288085. The cubic root of 23991571 is about 288.4161414362.

The spelling of 23991571 in words is "twenty-three million, nine hundred ninety-one thousand, five hundred seventy-one".