28897740 has 72 divisors (see below), whose sum is σ = 90046320. Its totient is φ = 7496064.

The previous prime is 28897721. The next prime is 28897741. The reversal of 28897740 is 4779882.

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 (28897741) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4491 + ... + 8829.

Almost surely, 2^28897740 is an apocalyptic number.

28897740 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 28897740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45023160).

28897740 is an abundant number, since it is smaller than the sum of its proper divisors (61148580).

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

28897740 is a wasteful number, since it uses less digits than its factorization.

28897740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4391 (or 4386 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 28897740 is about 5375.6618197204. The cubic root of 28897740 is about 306.8701364469.

The spelling of 28897740 in words is "twenty-eight million, eight hundred ninety-seven thousand, seven hundred forty".