90774640 has 80 divisors (see below), whose sum is σ = 238243680. Its totient is φ = 31861760.

The previous prime is 90774631. The next prime is 90774641. The reversal of 90774640 is 4647709.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 90774640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90774641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23742 + ... + 27298.

It is an arithmetic number, because the mean of its divisors is an integer number (2978046).

Almost surely, 2^90774640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90774640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119121840).

90774640 is an abundant number, since it is smaller than the sum of its proper divisors (147469040).

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

90774640 is a wasteful number, since it uses less digits than its factorization.

90774640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3610 (or 3604 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 90774640 is about 9527.5726184585. The cubic root of 90774640 is about 449.4225350020.

The spelling of 90774640 in words is "ninety million, seven hundred seventy-four thousand, six hundred forty".