161558115840 has 1200 divisors, whose sum is σ = 654310996416. Its totient is φ = 38052495360.

The previous prime is 161558115833. The next prime is 161558115863. The reversal of 161558115840 is 48511855161.

161558115840 is a `hidden beast` number, since 1 + 6 + 1 + 5 + 58 + 11 + 584 + 0 = 666.

It is a super-2 number, since 2×161558115840² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1179256252 + ... + 1179256388.

Almost surely, 2^161558115840 is an apocalyptic number.

161558115840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161558115840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (327155498208).

161558115840 is an abundant number, since it is smaller than the sum of its proper divisors (492752880576).

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

161558115840 is a wasteful number, since it uses less digits than its factorization.

161558115840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241 (or 205 counting only the distinct ones).

The product of its (nonzero) digits is 192000, while the sum is 45.

The spelling of 161558115840 in words is "one hundred sixty-one billion, five hundred fifty-eight million, one hundred fifteen thousand, eight hundred forty".