161601115111500 has 96 divisors (see below), whose sum is σ = 470945276657856. Its totient is φ = 43060404556800.

The previous prime is 161601115111481. The next prime is 161601115111511. The reversal of 161601115111500 is 5111511106161.

It is a happy number.

It is a super-2 number, since 2×161601115111500² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39586527 + ... + 43477526.

It is an arithmetic number, because the mean of its divisors is an integer number (4905679965186).

Almost surely, 2^{161601115111500} is an apocalyptic number.

161601115111500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161601115111500 is an abundant number, since it is smaller than the sum of its proper divisors (309344161546356).

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

161601115111500 is a wasteful number, since it uses less digits than its factorization.

161601115111500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83065372 (or 83065360 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 30.

Adding to 161601115111500 its reverse (5111511106161), we get a palindrome (166712626217661).

The spelling of 161601115111500 in words is "one hundred sixty-one trillion, six hundred one billion, one hundred fifteen million, one hundred eleven thousand, five hundred".