84431531 has 2 divisors, whose sum is σ = 84431532. Its totient is φ = 84431530.

The previous prime is 84431483. The next prime is 84431533. The reversal of 84431531 is 13513448.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 84431531 - 2⁶ = 84431467 is a prime.

It is a super-2 number, since 2×84431531² = 14257366854007922, which contains 22 as substring.

Together with 84431533, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 84431494 and 84431503.

It is not a weakly prime, because it can be changed into another prime (84431533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42215765 + 42215766.

It is an arithmetic number, because the mean of its divisors is an integer number (42215766).

Almost surely, 2^84431531 is an apocalyptic number.

84431531 is a deficient number, since it is larger than the sum of its proper divisors (1).

84431531 is an equidigital number, since it uses as much as digits as its factorization.

84431531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 29.

The square root of 84431531 is about 9188.6631780689. The cubic root of 84431531 is about 438.7005930248.

Adding to 84431531 its reverse (13513448), we get a palindrome (97944979).

The spelling of 84431531 in words is "eighty-four million, four hundred thirty-one thousand, five hundred thirty-one".