11629681281 has 27 divisors (see below), whose sum is σ = 17011847619. Its totient is φ = 7655848272.

The previous prime is 11629681241. The next prime is 11629681289. The reversal of 11629681281 is 18218692611.

It is a happy number.

The square root of 11629681281 is 107841.

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

11629681281 is a `hidden beast` number, since 1 + 1 + 6 + 296 + 81 + 281 = 666.

11629681281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 8536096881 + 3093584400 = 92391^2 + 55620^2 .

It is not a de Polignac number, because 11629681281 - 2¹⁷ = 11629550209 is a prime.

It is a super-2 number, since 2×11629681281² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11629681289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 33322695 + ... + 33323043.

Almost surely, 2^11629681281 is an apocalyptic number.

11629681281 is the 107841-st square number.

11629681281 is the 53921-st centered octagonal number.

It is an amenable number.

11629681281 is a deficient number, since it is larger than the sum of its proper divisors (5382166338).

11629681281 is an frugal number, since it uses more digits than its factorization.

11629681281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910 (or 455 counting only the distinct ones).

The product of its digits is 82944, while the sum is 45.

Multiplying 11629681281 by its product of digits (82944), we get a square (964612284171264 = 31058208²).

The spelling of 11629681281 in words is "eleven billion, six hundred twenty-nine million, six hundred eighty-one thousand, two hundred eighty-one".