85640725 has 6 divisors (see below), whose sum is σ = 106194530. Its totient is φ = 68512560.

The previous prime is 85640699. The next prime is 85640729. The reversal of 85640725 is 52704658.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 19201924 + 66438801 = 4382^2 + 8151^2 .

It is not a de Polignac number, because 85640725 - 2⁹ = 85640213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85640729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1712790 + ... + 1712839.

Almost surely, 2^85640725 is an apocalyptic number.

It is an amenable number.

85640725 is a deficient number, since it is larger than the sum of its proper divisors (20553805).

85640725 is a wasteful number, since it uses less digits than its factorization.

85640725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3425639 (or 3425634 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 37.

The square root of 85640725 is about 9254.2274123775. The cubic root of 85640725 is about 440.7849710045.

The spelling of 85640725 in words is "eighty-five million, six hundred forty thousand, seven hundred twenty-five".