11651861 has 4 divisors (see below), whose sum is σ = 12548172. Its totient is φ = 10755552.

The previous prime is 11651833. The next prime is 11651863. The reversal of 11651861 is 16815611.

11651861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16815611 = 2393 ⋅7027.

It can be written as a sum of positive squares in 2 ways, for example, as 6838225 + 4813636 = 2615^2 + 2194^2 .

It is a cyclic number.

It is not a de Polignac number, because 11651861 - 2⁶ = 11651797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11651863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448136 + ... + 448161.

It is an arithmetic number, because the mean of its divisors is an integer number (3137043).

Almost surely, 2^11651861 is an apocalyptic number.

It is an amenable number.

11651861 is a deficient number, since it is larger than the sum of its proper divisors (896311).

11651861 is an equidigital number, since it uses as much as digits as its factorization.

11651861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896310.

The product of its digits is 1440, while the sum is 29.

The square root of 11651861 is about 3413.4822395905. The cubic root of 11651861 is about 226.7070878989.

The spelling of 11651861 in words is "eleven million, six hundred fifty-one thousand, eight hundred sixty-one".