1661331120023 has 2 divisors, whose sum is σ = 1661331120024. Its totient is φ = 1661331120022.

The previous prime is 1661331119977. The next prime is 1661331120037. The reversal of 1661331120023 is 3200211331661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1661331120023 - 2³² = 1657036152727 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661331180023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830665560011 + 830665560012.

It is an arithmetic number, because the mean of its divisors is an integer number (830665560012).

Almost surely, 2^{1661331120023} is an apocalyptic number.

1661331120023 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661331120023 is an equidigital number, since it uses as much as digits as its factorization.

1661331120023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 29.

Adding to 1661331120023 its reverse (3200211331661), we get a palindrome (4861542451684).

The spelling of 1661331120023 in words is "one trillion, six hundred sixty-one billion, three hundred thirty-one million, one hundred twenty thousand, twenty-three".