85509405 has 128 divisors (see below), whose sum is σ = 177292800. Its totient is φ = 38817792.

The previous prime is 85509401. The next prime is 85509421. The reversal of 85509405 is 50490558.

It is a happy number.

It is not a de Polignac number, because 85509405 - 2² = 85509401 is a prime.

85509405 is a modest number, since divided by 9405 gives 8550 as remainder.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 85509405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85509401) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1613359 + ... + 1613411.

It is an arithmetic number, because the mean of its divisors is an integer number (1385100).

Almost surely, 2^85509405 is an apocalyptic number.

85509405 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

85509405 is an abundant number, since it is smaller than the sum of its proper divisors (91783395).

85509405 is a wasteful number, since it uses less digits than its factorization.

85509405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 85509405 is about 9247.1295546240. The cubic root of 85509405 is about 440.5595584115.

It can be divided in two parts, 8550 and 9405, that added together give a triangular number (17955 = T₁₈₉).

The spelling of 85509405 in words is "eighty-five million, five hundred nine thousand, four hundred five".