90820880640 has 1296 divisors, whose sum is σ = 389313812160. Its totient is φ = 20205158400.

The previous prime is 90820880599. The next prime is 90820880677. The reversal of 90820880640 is 4608802809.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1296).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 899216590 + ... + 899216690.

It is an arithmetic number, because the mean of its divisors is an integer number (300396460).

Almost surely, 2^90820880640 is an apocalyptic number.

90820880640 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 90820880640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194656906080).

90820880640 is an abundant number, since it is smaller than the sum of its proper divisors (298492931520).

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

90820880640 is a wasteful number, since it uses less digits than its factorization.

90820880640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The spelling of 90820880640 in words is "ninety billion, eight hundred twenty million, eight hundred eighty thousand, six hundred forty".