11959390881 has 45 divisors (see below), whose sum is σ = 18546813571. Its totient is φ = 7679626416.

The previous prime is 11959390879. The next prime is 11959390909. The reversal of 11959390881 is 18809395911.

The square root of 11959390881 is 109359.

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., 6271214481 + 5688176400 = 79191^2 + 75420^2 .

It is not a de Polignac number, because 11959390881 - 2¹ = 11959390879 is a prime.

It is a super-2 number, since 2×11959390881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11959390181) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 28542490 + ... + 28542908.

Almost surely, 2^11959390881 is an apocalyptic number.

11959390881 is the 109359-th square number.

11959390881 is the 54680-th centered octagonal number.

It is an amenable number.

11959390881 is a deficient number, since it is larger than the sum of its proper divisors (6587422690).

11959390881 is an frugal number, since it uses more digits than its factorization.

11959390881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 908 (or 451 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 54.

The spelling of 11959390881 in words is "eleven billion, nine hundred fifty-nine million, three hundred ninety thousand, eight hundred eighty-one".