161027591 has 2 divisors, whose sum is σ = 161027592. Its totient is φ = 161027590.

The previous prime is 161027557. The next prime is 161027597. The reversal of 161027591 is 195720161.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161027591 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161027597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80513795 + 80513796.

It is an arithmetic number, because the mean of its divisors is an integer number (80513796).

Almost surely, 2^161027591 is an apocalyptic number.

161027591 is a deficient number, since it is larger than the sum of its proper divisors (1).

161027591 is an equidigital number, since it uses as much as digits as its factorization.

161027591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3780, while the sum is 32.

The square root of 161027591 is about 12689.6647315837. The cubic root of 161027591 is about 544.0432570400.

The spelling of 161027591 in words is "one hundred sixty-one million, twenty-seven thousand, five hundred ninety-one".