90506640 has 160 divisors (see below), whose sum is σ = 339621120. Its totient is φ = 19464192.

The previous prime is 90506629. The next prime is 90506659. The reversal of 90506640 is 4660509.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 90506598 and 90506607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26976 + ... + 30144.

It is an arithmetic number, because the mean of its divisors is an integer number (2122632).

Almost surely, 2^90506640 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 90506640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169810560).

90506640 is an abundant number, since it is smaller than the sum of its proper divisors (249114480).

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

90506640 is a wasteful number, since it uses less digits than its factorization.

90506640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3209 (or 3203 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 90506640 is about 9513.4977794710. The cubic root of 90506640 is about 448.9798123539.

The spelling of 90506640 in words is "ninety million, five hundred six thousand, six hundred forty".