161553199626 has 384 divisors, whose sum is σ = 460254412800. Its totient is φ = 42199932096.

The previous prime is 161553199603. The next prime is 161553199627. The reversal of 161553199626 is 626991355161.

161553199626 is a `hidden beast` number, since 1 + 6 + 1 + 5 + 5 + 3 + 1 + 9 + 9 + 626 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (161553199627) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 275218105 + ... + 275218691.

It is an arithmetic number, because the mean of its divisors is an integer number (1198579200).

Almost surely, 2^161553199626 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161553199626, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230127206400).

161553199626 is an abundant number, since it is smaller than the sum of its proper divisors (298701213174).

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

161553199626 is a wasteful number, since it uses less digits than its factorization.

161553199626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765 (or 739 counting only the distinct ones).

The product of its digits is 2624400, while the sum is 54.

The spelling of 161553199626 in words is "one hundred sixty-one billion, five hundred fifty-three million, one hundred ninety-nine thousand, six hundred twenty-six".