11861999316 has 66 divisors (see below), whose sum is σ = 31138192442. Its totient is φ = 3953921040.

The previous prime is 11861999291. The next prime is 11861999327. The reversal of 11861999316 is 61399916811.

It is a happy number.

11861999316 is a `hidden beast` number, since 1 + 1 + 8 + 619 + 9 + 9 + 3 + 16 = 666.

It can be written as a sum of positive squares in only one way, i.e., 8171436816 + 3690562500 = 90396^2 + 60750^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 21 ways as a sum of consecutive naturals, for example, 211086 + ... + 261306.

Almost surely, 2^11861999316 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11861999316, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15569096221).

11861999316 is an abundant number, since it is smaller than the sum of its proper divisors (19276193126).

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

11861999316 is an frugal number, since it uses more digits than its factorization.

11861999316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50255 (or 50226 counting only the distinct ones).

The product of its digits is 629856, while the sum is 54.

The spelling of 11861999316 in words is "eleven billion, eight hundred sixty-one million, nine hundred ninety-nine thousand, three hundred sixteen".