11856814321 has 27 divisors (see below), whose sum is σ = 13781181099. Its totient is φ = 10192010400.

The previous prime is 11856814309. The next prime is 11856814351. The reversal of 11856814321 is 12341865811.

The square root of 11856814321 is 108889.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 3400172721 + 8456641600 = 58311^2 + 91960^2 .

It is not a de Polignac number, because 11856814321 - 2⁹ = 11856813809 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (11856814351) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 22757541 + ... + 22758061.

Almost surely, 2^11856814321 is an apocalyptic number.

11856814321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11856814321 is the 108889-th square number.

11856814321 is the 54445-th centered octagonal number.

It is an amenable number.

11856814321 is a deficient number, since it is larger than the sum of its proper divisors (1924366778).

11856814321 is an frugal number, since it uses more digits than its factorization.

11856814321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1102 (or 551 counting only the distinct ones).

The product of its digits is 46080, while the sum is 40.

The spelling of 11856814321 in words is "eleven billion, eight hundred fifty-six million, eight hundred fourteen thousand, three hundred twenty-one".