85215840 has 48 divisors (see below), whose sum is σ = 268431408. Its totient is φ = 22724096.

The previous prime is 85215839. The next prime is 85215853. The reversal of 85215840 is 4851258.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88287 + ... + 89246.

It is an arithmetic number, because the mean of its divisors is an integer number (5592321).

Almost surely, 2^85215840 is an apocalyptic number.

85215840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

85215840 is an abundant number, since it is smaller than the sum of its proper divisors (183215568).

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

85215840 is a wasteful number, since it uses less digits than its factorization.

85215840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177551 (or 177543 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 33.

The square root of 85215840 is about 9231.2426032469. The cubic root of 85215840 is about 440.0548141078.

The spelling of 85215840 in words is "eighty-five million, two hundred fifteen thousand, eight hundred forty".