85640129 has 4 divisors (see below), whose sum is σ = 86846400. Its totient is φ = 84433860.

The previous prime is 85640119. The next prime is 85640143. The reversal of 85640129 is 92104658.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85640129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85640119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 603029 + ... + 603170.

It is an arithmetic number, because the mean of its divisors is an integer number (21711600).

Almost surely, 2^85640129 is an apocalyptic number.

It is an amenable number.

85640129 is a deficient number, since it is larger than the sum of its proper divisors (1206271).

85640129 is a wasteful number, since it uses less digits than its factorization.

85640129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1206270.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 85640129 is about 9254.1952108220. The cubic root of 85640129 is about 440.7839484830.

The spelling of 85640129 in words is "eighty-five million, six hundred forty thousand, one hundred twenty-nine".