90045540 has 192 divisors, whose sum is σ = 307077120. Its totient is φ = 21772800.

The previous prime is 90045533. The next prime is 90045547. The reversal of 90045540 is 4554009.

It is an interprime number because it is at equal distance from previous prime (90045533) and next prime (90045547).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (90045547) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 708957 + ... + 709083.

It is an arithmetic number, because the mean of its divisors is an integer number (1599360).

Almost surely, 2^90045540 is an apocalyptic number.

90045540 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 90045540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153538560).

90045540 is an abundant number, since it is smaller than the sum of its proper divisors (217031580).

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

90045540 is a wasteful number, since it uses less digits than its factorization.

90045540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 90045540 is about 9489.2328457047. The cubic root of 90045540 is about 448.2160482705.

Adding to 90045540 its reverse (4554009), we get a palindrome (94599549).

The spelling of 90045540 in words is "ninety million, forty-five thousand, five hundred forty".