11621670561 has 16 divisors (see below), whose sum is σ = 17332848000. Its totient is φ = 7695779184.

The previous prime is 11621670547. The next prime is 11621670563. The reversal of 11621670561 is 16507612611.

It is a happy number.

11621670561 is a `hidden beast` number, since 1 + 1 + 6 + 21 + 6 + 70 + 561 = 666.

11621670561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11621670561 - 2²¹ = 11619573409 is a prime.

It is a super-3 number, since 3×11621670561³ (a number of 31 digits) contains 333 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11621670563) 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 15 ways as a sum of consecutive naturals, for example, 1440381 + ... + 1448426.

It is an arithmetic number, because the mean of its divisors is an integer number (1083303000).

Almost surely, 2^11621670561 is an apocalyptic number.

It is an amenable number.

11621670561 is a deficient number, since it is larger than the sum of its proper divisors (5711177439).

11621670561 is a wasteful number, since it uses less digits than its factorization.

11621670561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2888965 (or 2888959 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The spelling of 11621670561 in words is "eleven billion, six hundred twenty-one million, six hundred seventy thousand, five hundred sixty-one".