1861131168 has 504 divisors, whose sum is σ = 6611290308. Its totient is φ = 510603264.

The previous prime is 1861131133. The next prime is 1861131169. The reversal of 1861131168 is 8611311681.

1861131168 is a `hidden beast` number, since 1 + 8 + 611 + 31 + 1 + 6 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1856920464 + 4210704 = 43092^2 + 2052^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (6912) is a multiple of the sum of its prime divisors (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861131169) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 97954263 + ... + 97954281.

Almost surely, 2^1861131168 is an apocalyptic number.

1861131168 is a gapful number since it is divisible by the number (18) 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 1861131168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3305645154).

1861131168 is an abundant number, since it is smaller than the sum of its proper divisors (4750159140).

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

1861131168 is a wasteful number, since it uses less digits than its factorization.

1861131168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 54 counting only the distinct ones).

The product of its digits is 6912, while the sum is 36.

The square root of 1861131168 is about 43140.8294774220. The cubic root of 1861131168 is about 1230.0582006964.

The spelling of 1861131168 in words is "one billion, eight hundred sixty-one million, one hundred thirty-one thousand, one hundred sixty-eight".