161266989 has 16 divisors (see below), whose sum is σ = 232569792. Its totient is φ = 98809728.

The previous prime is 161266921. The next prime is 161266993. The reversal of 161266989 is 989662161.

It is not a de Polignac number, because 161266989 - 2⁸ = 161266733 is a prime.

It is a super-2 number, since 2×161266989² = 52014083482252242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161266909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 214 + ... + 17960.

It is an arithmetic number, because the mean of its divisors is an integer number (14535612).

Almost surely, 2^161266989 is an apocalyptic number.

It is an amenable number.

161266989 is a deficient number, since it is larger than the sum of its proper divisors (71302803).

161266989 is a wasteful number, since it uses less digits than its factorization.

161266989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17996.

The product of its digits is 279936, while the sum is 48.

The square root of 161266989 is about 12699.0940228034. The cubic root of 161266989 is about 544.3127313095.

The spelling of 161266989 in words is "one hundred sixty-one million, two hundred sixty-six thousand, nine hundred eighty-nine".