43431091 has 4 divisors (see below), whose sum is σ = 47379384. Its totient is φ = 39482800.

The previous prime is 43431053. The next prime is 43431103. The reversal of 43431091 is 19013434.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 43431091 - 2¹⁵ = 43398323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43431191) 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, 1974130 + ... + 1974151.

It is an arithmetic number, because the mean of its divisors is an integer number (11844846).

Almost surely, 2^43431091 is an apocalyptic number.

43431091 is a deficient number, since it is larger than the sum of its proper divisors (3948293).

43431091 is a wasteful number, since it uses less digits than its factorization.

43431091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3948292.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 43431091 is about 6590.2269308424. The cubic root of 43431091 is about 351.5066775473.

It can be divided in two parts, 43 and 431091, that added together give a palindrome (431134).

The spelling of 43431091 in words is "forty-three million, four hundred thirty-one thousand, ninety-one".