90685440 has 240 divisors, whose sum is σ = 330291360. Its totient is φ = 23592960.

The previous prime is 90685433. The next prime is 90685451. The reversal of 90685440 is 4458609.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 90685395 and 90685404.

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, 2211820 + ... + 2211860.

It is an arithmetic number, because the mean of its divisors is an integer number (1376214).

Almost surely, 2^90685440 is an apocalyptic number.

90685440 is a gapful number since it is divisible by the number (90) 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 90685440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (165145680).

90685440 is an abundant number, since it is smaller than the sum of its proper divisors (239605920).

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

90685440 is an equidigital number, since it uses as much as digits as its factorization.

90685440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 90685440 is about 9522.8903175454. The cubic root of 90685440 is about 449.2752779108.

It can be divided in two parts, 90685 and 440, that added together give a cube (91125 = 45³).

The spelling of 90685440 in words is "ninety million, six hundred eighty-five thousand, four hundred forty".