297728640 has 384 divisors, whose sum is σ = 1160939520. Its totient is φ = 69672960.

The previous prime is 297728621. The next prime is 297728647. The reversal of 297728640 is 46827792.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (297728647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2344257 + ... + 2344383.

It is an arithmetic number, because the mean of its divisors is an integer number (3023280).

Almost surely, 2^297728640 is an apocalyptic number.

297728640 is a gapful number since it is divisible by the number (20) 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 297728640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (580469760).

297728640 is an abundant number, since it is smaller than the sum of its proper divisors (863210880).

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

297728640 is a wasteful number, since it uses less digits than its factorization.

297728640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 185 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The square root of 297728640 is about 17254.8149801729. The cubic root of 297728640 is about 667.7391980338.

The spelling of 297728640 in words is "two hundred ninety-seven million, seven hundred twenty-eight thousand, six hundred forty".