9861431 has 2 divisors, whose sum is σ = 9861432. Its totient is φ = 9861430.

The previous prime is 9861413. The next prime is 9861433. The reversal of 9861431 is 1341689.

It is a happy number.

Together with previous prime (9861413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (1341689) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9861431 - 2⁶ = 9861367 is a prime.

It is a super-2 number, since 2×9861431² = 194495642735522, which contains 22 as substring.

Together with 9861433, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9861433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4930715 + 4930716.

It is an arithmetic number, because the mean of its divisors is an integer number (4930716).

Almost surely, 2^9861431 is an apocalyptic number.

9861431 is a deficient number, since it is larger than the sum of its proper divisors (1).

9861431 is an equidigital number, since it uses as much as digits as its factorization.

9861431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 32.

The square root of 9861431 is about 3140.2915469746. The cubic root of 9861431 is about 214.4437106315.

The spelling of 9861431 in words is "nine million, eight hundred sixty-one thousand, four hundred thirty-one".