161823554919 has 32 divisors (see below), whose sum is σ = 259132876800. Its totient is φ = 99216200160.

The previous prime is 161823554911. The next prime is 161823554983. The reversal of 161823554919 is 919455328161.

161823554919 is a `hidden beast` number, since 1 + 6 + 1 + 82 + 3 + 5 + 549 + 19 = 666.

It is not a de Polignac number, because 161823554919 - 2³ = 161823554911 is a prime.

It is a super-2 number, since 2×161823554919² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161823554911) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 755499 + ... + 945740.

It is an arithmetic number, because the mean of its divisors is an integer number (8097902400).

Almost surely, 2^161823554919 is an apocalyptic number.

161823554919 is a deficient number, since it is larger than the sum of its proper divisors (97309321881).

161823554919 is a wasteful number, since it uses less digits than its factorization.

161823554919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1701532 (or 1701526 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 54.

The spelling of 161823554919 in words is "one hundred sixty-one billion, eight hundred twenty-three million, five hundred fifty-four thousand, nine hundred nineteen".