161263009 has 2 divisors, whose sum is σ = 161263010. Its totient is φ = 161263008.

The previous prime is 161263007. The next prime is 161263027. The reversal of 161263009 is 900362161.

161263009 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 can be written as a sum of positive squares in only one way, i.e., 154256400 + 7006609 = 12420^2 + 2647^2 .

It is an emirp because it is prime and its reverse (900362161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161263009 - 2¹ = 161263007 is a prime.

Together with 161263007, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (161263007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80631504 + 80631505.

It is an arithmetic number, because the mean of its divisors is an integer number (80631505).

Almost surely, 2^161263009 is an apocalyptic number.

It is an amenable number.

161263009 is a deficient number, since it is larger than the sum of its proper divisors (1).

161263009 is an equidigital number, since it uses as much as digits as its factorization.

161263009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 161263009 is about 12698.9373177443. The cubic root of 161263009 is about 544.3082534712.

The spelling of 161263009 in words is "one hundred sixty-one million, two hundred sixty-three thousand, nine".