161521110 has 24 divisors (see below), whose sum is σ = 419955120. Its totient is φ = 43072272.

The previous prime is 161521091. The next prime is 161521117. The reversal of 161521110 is 11125161.

It is a happy number.

161521110 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161521117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 897250 + ... + 897429.

It is an arithmetic number, because the mean of its divisors is an integer number (17498130).

Almost surely, 2^161521110 is an apocalyptic number.

161521110 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161521110 is an abundant number, since it is smaller than the sum of its proper divisors (258434010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161521110 is a wasteful number, since it uses less digits than its factorization.

161521110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1794692 (or 1794689 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 18.

The square root of 161521110 is about 12709.0955618407. The cubic root of 161521110 is about 544.5984866386.

Adding to 161521110 its reverse (11125161), we get a palindrome (172646271).

The spelling of 161521110 in words is "one hundred sixty-one million, five hundred twenty-one thousand, one hundred ten".