90205540 has 48 divisors (see below), whose sum is σ = 208091520. Its totient is φ = 32693760.

The previous prime is 90205501. The next prime is 90205541. The reversal of 90205540 is 4550209.

It is not an unprimeable number, because it can be changed into a prime (90205541) 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, 3580 + ... + 13900.

It is an arithmetic number, because the mean of its divisors is an integer number (4335240).

Almost surely, 2^90205540 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 90205540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104045760).

90205540 is an abundant number, since it is smaller than the sum of its proper divisors (117885980).

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

90205540 is a wasteful number, since it uses less digits than its factorization.

90205540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10372 (or 10370 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 90205540 is about 9497.6597117395. The cubic root of 90205540 is about 448.4813663661.

Adding to 90205540 its reverse (4550209), we get a palindrome (94755749).

The spelling of 90205540 in words is "ninety million, two hundred five thousand, five hundred forty".