1231975571 has 2 divisors, whose sum is σ = 1231975572. Its totient is φ = 1231975570.

The previous prime is 1231975553. The next prime is 1231975579. The reversal of 1231975571 is 1755791321.

It is a strong prime.

It is an emirp because it is prime and its reverse (1755791321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1231975571 - 2¹⁴ = 1231959187 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1231975579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615987785 + 615987786.

It is an arithmetic number, because the mean of its divisors is an integer number (615987786).

Almost surely, 2^1231975571 is an apocalyptic number.

1231975571 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231975571 is an equidigital number, since it uses as much as digits as its factorization.

1231975571 is an evil number, because the sum of its binary digits is even.

The product of its digits is 66150, while the sum is 41.

The square root of 1231975571 is about 35099.5095549781. The cubic root of 1231975571 is about 1072.0145965354.

The spelling of 1231975571 in words is "one billion, two hundred thirty-one million, nine hundred seventy-five thousand, five hundred seventy-one".