43491531 has 16 divisors (see below), whose sum is σ = 58830848. Its totient is φ = 28576800.

The previous prime is 43491527. The next prime is 43491587. The reversal of 43491531 is 13519434.

43491531 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 43491531 - 2² = 43491527 is a prime.

It is a super-2 number, since 2×43491531² = 3783026537447922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43491131) 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 15 ways as a sum of consecutive naturals, for example, 80121 + ... + 80661.

It is an arithmetic number, because the mean of its divisors is an integer number (3676928).

Almost surely, 2^43491531 is an apocalyptic number.

43491531 is a deficient number, since it is larger than the sum of its proper divisors (15339317).

43491531 is a wasteful number, since it uses less digits than its factorization.

43491531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 882.

The product of its digits is 6480, while the sum is 30.

The square root of 43491531 is about 6594.8109146510. The cubic root of 43491531 is about 351.6696576891.

The spelling of 43491531 in words is "forty-three million, four hundred ninety-one thousand, five hundred thirty-one".