85641780 has 48 divisors (see below), whose sum is σ = 274055040. Its totient is φ = 19575168.

The previous prime is 85641769. The next prime is 85641793. The reversal of 85641780 is 8714658.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 101535 + ... + 102374.

It is an arithmetic number, because the mean of its divisors is an integer number (5709480).

Almost surely, 2^85641780 is an apocalyptic number.

It is an amenable number.

85641780 is an abundant number, since it is smaller than the sum of its proper divisors (188413260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

85641780 is a wasteful number, since it uses less digits than its factorization.

85641780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203928 (or 203926 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 39.

The square root of 85641780 is about 9254.2844131786. The cubic root of 85641780 is about 440.7867809932.

The spelling of 85641780 in words is "eighty-five million, six hundred forty-one thousand, seven hundred eighty".