161798889 has 64 divisors (see below), whose sum is σ = 272629760. Its totient is φ = 83280960.

The previous prime is 161798887. The next prime is 161798893. The reversal of 161798889 is 988897161.

It is not a de Polignac number, because 161798889 - 2¹ = 161798887 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161798887) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1273944 + ... + 1274070.

It is an arithmetic number, because the mean of its divisors is an integer number (4259840).

Almost surely, 2^161798889 is an apocalyptic number.

161798889 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

161798889 is a deficient number, since it is larger than the sum of its proper divisors (110830871).

161798889 is a wasteful number, since it uses less digits than its factorization.

161798889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290.

The product of its digits is 1741824, while the sum is 57.

The square root of 161798889 is about 12720.0192216836. The cubic root of 161798889 is about 544.9105023760.

The spelling of 161798889 in words is "one hundred sixty-one million, seven hundred ninety-eight thousand, eight hundred eighty-nine".