861238490112 has 2640 divisors, whose sum is σ = 3719061916416. Its totient is φ = 192695500800.

The previous prime is 861238490107. The next prime is 861238490219. The reversal of 861238490112 is 211094832168.

861238490112 is a `hidden beast` number, since 8 + 6 + 12 + 38 + 490 + 112 = 666.

It is a super-3 number, since 3×861238490112³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 21005816812 + ... + 21005816852.

Almost surely, 2^861238490112 is an apocalyptic number.

861238490112 is a gapful number since it is divisible by the number (82) 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 861238490112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1859530958208).

861238490112 is an abundant number, since it is smaller than the sum of its proper divisors (2857823426304).

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

861238490112 is a wasteful number, since it uses less digits than its factorization.

861238490112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 861238490112 in words is "eight hundred sixty-one billion, two hundred thirty-eight million, four hundred ninety thousand, one hundred twelve".