90399720 has 128 divisors (see below), whose sum is σ = 294912000. Its totient is φ = 22083840.

The previous prime is 90399713. The next prime is 90399731. The reversal of 90399720 is 2799309.

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, 70041 + ... + 71319.

It is an arithmetic number, because the mean of its divisors is an integer number (2304000).

Almost surely, 2^90399720 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 90399720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147456000).

90399720 is an abundant number, since it is smaller than the sum of its proper divisors (204512280).

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

90399720 is a wasteful number, since it uses less digits than its factorization.

90399720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 30618, while the sum is 39.

The square root of 90399720 is about 9507.8767345817. The cubic root of 90399720 is about 448.8029419515.

It can be divided in two parts, 90399 and 720, that added together give a palindrome (91119).

The spelling of 90399720 in words is "ninety million, three hundred ninety-nine thousand, seven hundred twenty".