161563224520 has 32 divisors (see below), whose sum is σ = 375243621120. Its totient is φ = 62540602560.

The previous prime is 161563224469. The next prime is 161563224539. The reversal of 161563224520 is 25422365161.

It is a super-2 number, since 2×161563224520² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161563224520.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65145222 + ... + 65147701.

It is an arithmetic number, because the mean of its divisors is an integer number (11726363160).

Almost surely, 2^161563224520 is an apocalyptic number.

161563224520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161563224520 is an abundant number, since it is smaller than the sum of its proper divisors (213680396600).

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

161563224520 is a wasteful number, since it uses less digits than its factorization.

161563224520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130292965 (or 130292961 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

Adding to 161563224520 its reverse (25422365161), we get a palindrome (186985589681).

The spelling of 161563224520 in words is "one hundred sixty-one billion, five hundred sixty-three million, two hundred twenty-four thousand, five hundred twenty".