90078589440 has 720 divisors, whose sum is σ = 368208774648. Its totient is φ = 20288765952.

The previous prime is 90078589439. The next prime is 90078589441. The reversal of 90078589440 is 4498587009.

It is an interprime number because it is at equal distance from previous prime (90078589439) and next prime (90078589441).

It can be written as a sum of positive squares in 4 ways, for example, as 89224079616 + 854509824 = 298704^2 + 29232^2 .

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×90078589440² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (90078589441) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 82413534 + ... + 82414626.

Almost surely, 2^90078589440 is an apocalyptic number.

90078589440 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 90078589440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184104387324).

90078589440 is an abundant number, since it is smaller than the sum of its proper divisors (278130185208).

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

90078589440 is a wasteful number, since it uses less digits than its factorization.

90078589440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209 (or 1183 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 90078589440 in words is "ninety billion, seventy-eight million, five hundred eighty-nine thousand, four hundred forty".