43087531 has 2 divisors, whose sum is σ = 43087532. Its totient is φ = 43087530.

The previous prime is 43087529. The next prime is 43087543. The reversal of 43087531 is 13578034.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 43087531 - 2¹ = 43087529 is a prime.

It is a super-2 number, since 2×43087531² = 3713070655351922, which contains 22 as substring.

Together with 43087529, it forms a pair of twin primes.

It is equal to p_2609509 and since 43087531 and 2609509 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 43087493 and 43087502.

It is not a weakly prime, because it can be changed into another prime (43087831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21543765 + 21543766.

It is an arithmetic number, because the mean of its divisors is an integer number (21543766).

Almost surely, 2^43087531 is an apocalyptic number.

43087531 is a deficient number, since it is larger than the sum of its proper divisors (1).

43087531 is an equidigital number, since it uses as much as digits as its factorization.

43087531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 43087531 is about 6564.1093074384. The cubic root of 43087531 is about 350.5773627006.

The spelling of 43087531 in words is "forty-three million, eighty-seven thousand, five hundred thirty-one".