90647920 has 80 divisors (see below), whose sum is σ = 231413760. Its totient is φ = 32748800.

The previous prime is 90647833. The next prime is 90647933. The reversal of 90647920 is 2974609.

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

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 90647920.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 210105 + ... + 210535.

It is an arithmetic number, because the mean of its divisors is an integer number (2892672).

Almost surely, 2^90647920 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 90647920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115706880).

90647920 is an abundant number, since it is smaller than the sum of its proper divisors (140765840).

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

90647920 is a wasteful number, since it uses less digits than its factorization.

90647920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 694 (or 688 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 90647920 is about 9520.9201236015. The cubic root of 90647920 is about 449.2133086328.

The spelling of 90647920 in words is "ninety million, six hundred forty-seven thousand, nine hundred twenty".