85131643 has 2 divisors, whose sum is σ = 85131644. Its totient is φ = 85131642.

The previous prime is 85131637. The next prime is 85131653. The reversal of 85131643 is 34613158.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 85131643 - 2²¹ = 83034491 is a prime.

It is not a weakly prime, because it can be changed into another prime (85131623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42565821 + 42565822.

It is an arithmetic number, because the mean of its divisors is an integer number (42565822).

Almost surely, 2^85131643 is an apocalyptic number.

85131643 is a deficient number, since it is larger than the sum of its proper divisors (1).

85131643 is an equidigital number, since it uses as much as digits as its factorization.

85131643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 31.

The square root of 85131643 is about 9226.6810392470. The cubic root of 85131643 is about 439.9098351748.

The spelling of 85131643 in words is "eighty-five million, one hundred thirty-one thousand, six hundred forty-three".