85389440 has 64 divisors (see below), whose sum is σ = 206311320. Its totient is φ = 33792000.

The previous prime is 85389431. The next prime is 85389449. The reversal of 85389440 is 4498358.

It is an interprime number because it is at equal distance from previous prime (85389431) and next prime (85389449).

It can be written as a sum of positive squares in 4 ways, for example, as 84787264 + 602176 = 9208^2 + 776^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (85389449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63980 + ... + 65300.

Almost surely, 2^85389440 is an apocalyptic number.

85389440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 85389440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103155660).

85389440 is an abundant number, since it is smaller than the sum of its proper divisors (120921880).

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

85389440 is a wasteful number, since it uses less digits than its factorization.

85389440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1441 (or 1429 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 85389440 is about 9240.6406704297. The cubic root of 85389440 is about 440.3534350315.

The spelling of 85389440 in words is "eighty-five million, three hundred eighty-nine thousand, four hundred forty".