161541511 has 2 divisors, whose sum is σ = 161541512. Its totient is φ = 161541510.

The previous prime is 161541487. The next prime is 161541547. The reversal of 161541511 is 115145161.

161541511 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161541511 - 2¹⁹ = 161017223 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161541551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80770755 + 80770756.

It is an arithmetic number, because the mean of its divisors is an integer number (80770756).

Almost surely, 2^161541511 is an apocalyptic number.

161541511 is a deficient number, since it is larger than the sum of its proper divisors (1).

161541511 is an equidigital number, since it uses as much as digits as its factorization.

161541511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 600, while the sum is 25.

The square root of 161541511 is about 12709.8981506541. The cubic root of 161541511 is about 544.6214142629.

Adding to 161541511 its reverse (115145161), we get a palindrome (276686672).

The spelling of 161541511 in words is "one hundred sixty-one million, five hundred forty-one thousand, five hundred eleven".