161251340211 has 24 divisors (see below), whose sum is σ = 250863574416. Its totient is φ = 99220455360.

The previous prime is 161251340149. The next prime is 161251340219. The reversal of 161251340211 is 112043152161.

161251340211 is a `hidden beast` number, since 1 + 6 + 1 + 251 + 3 + 402 + 1 + 1 = 666.

It is not a de Polignac number, because 161251340211 - 2⁶ = 161251340147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161251340219) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1037841 + ... + 1183053.

It is an arithmetic number, because the mean of its divisors is an integer number (10452648934).

Almost surely, 2^161251340211 is an apocalyptic number.

161251340211 is a deficient number, since it is larger than the sum of its proper divisors (89612234205).

161251340211 is a wasteful number, since it uses less digits than its factorization.

161251340211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154723 (or 154720 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

Adding to 161251340211 its reverse (112043152161), we get a palindrome (273294492372).

The spelling of 161251340211 in words is "one hundred sixty-one billion, two hundred fifty-one million, three hundred forty thousand, two hundred eleven".