161906120121 has 16 divisors (see below), whose sum is σ = 227791716480. Its totient is φ = 102084428160.

The previous prime is 161906120113. The next prime is 161906120153. The reversal of 161906120121 is 121021609161.

It is not a de Polignac number, because 161906120121 - 2³ = 161906120113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161906127121) 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, 13176250 + ... + 13188531.

It is an arithmetic number, because the mean of its divisors is an integer number (14236982280).

Almost surely, 2^161906120121 is an apocalyptic number.

It is an amenable number.

161906120121 is a deficient number, since it is larger than the sum of its proper divisors (65885596359).

161906120121 is a wasteful number, since it uses less digits than its factorization.

161906120121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26364896.

The product of its (nonzero) digits is 1296, while the sum is 30.

Adding to 161906120121 its reverse (121021609161), we get a palindrome (282927729282).

The spelling of 161906120121 in words is "one hundred sixty-one billion, nine hundred six million, one hundred twenty thousand, one hundred twenty-one".