161291031300 has 972 divisors, whose sum is σ = 635395777380. Its totient is φ = 35389509120.

The previous prime is 161291031281. The next prime is 161291031301. The reversal of 161291031300 is 3130192161.

161291031300 is a `hidden beast` number, since 1 + 61 + 291 + 0 + 313 + 0 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 1955939076 + 159335092224 = 44226^2 + 399168^2 .

It is a tau number, because it is divible by the number of its divisors (972).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (161291031301) by changing a digit.

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 323 ways as a sum of consecutive naturals, for example, 932318014 + ... + 932318186.

Almost surely, 2^161291031300 is an apocalyptic number.

161291031300 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 161291031300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317697888690).

161291031300 is an abundant number, since it is smaller than the sum of its proper divisors (474104746080).

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

161291031300 is a wasteful number, since it uses less digits than its factorization.

161291031300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254 (or 219 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The spelling of 161291031300 in words is "one hundred sixty-one billion, two hundred ninety-one million, thirty-one thousand, three hundred".