43631261 has 4 divisors (see below), whose sum is σ = 43770972. Its totient is φ = 43491552.

The previous prime is 43631249. The next prime is 43631281. The reversal of 43631261 is 16213634.

43631261 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: 16213634 = 2 ⋅8106817.

It can be written as a sum of positive squares in 2 ways, for example, as 3308761 + 40322500 = 1819^2 + 6350^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43631261 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 43631261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43631281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69386 + ... + 70011.

It is an arithmetic number, because the mean of its divisors is an integer number (10942743).

Almost surely, 2^43631261 is an apocalyptic number.

It is an amenable number.

43631261 is a deficient number, since it is larger than the sum of its proper divisors (139711).

43631261 is a wasteful number, since it uses less digits than its factorization.

43631261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139710.

The product of its digits is 2592, while the sum is 26.

The square root of 43631261 is about 6605.3963544968. The cubic root of 43631261 is about 352.0458709375.

Adding to 43631261 its reverse (16213634), we get a palindrome (59844895).

The spelling of 43631261 in words is "forty-three million, six hundred thirty-one thousand, two hundred sixty-one".