11655145681 has 9 divisors (see below), whose sum is σ = 11913590299. Its totient is φ = 11402197744.

The previous prime is 11655145673. The next prime is 11655145687. The reversal of 11655145681 is 18654155611.

The square root of 11655145681 is 107959.

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., 5479700625 + 6175445056 = 74025^2 + 78584^2 .

It is not a de Polignac number, because 11655145681 - 2³ = 11655145673 is a prime.

It is a super-2 number, since 2×11655145681² (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 (11655145687) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5072925 + ... + 5075221.

Almost surely, 2^11655145681 is an apocalyptic number.

11655145681 is the 107959-th square number.

11655145681 is the 53980-th centered octagonal number.

It is an amenable number.

11655145681 is a deficient number, since it is larger than the sum of its proper divisors (258444618).

11655145681 is an frugal number, since it uses more digits than its factorization.

11655145681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4688 (or 2344 counting only the distinct ones).

The product of its digits is 144000, while the sum is 43.

The spelling of 11655145681 in words is "eleven billion, six hundred fifty-five million, one hundred forty-five thousand, six hundred eighty-one".