28887940 has 24 divisors (see below), whose sum is σ = 60788952. Its totient is φ = 11531520.

The previous prime is 28887917. The next prime is 28887941. The reversal of 28887940 is 4978882.

It can be written as a sum of positive squares in 4 ways, for example, as 244036 + 28643904 = 494^2 + 5352^2 .

It is a super-4 number, since 4×28887940⁴ (a number of 31 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (28887941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11170 + ... + 13510.

It is an arithmetic number, because the mean of its divisors is an integer number (2532873).

Almost surely, 2^28887940 is an apocalyptic number.

28887940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28887940 is an abundant number, since it is smaller than the sum of its proper divisors (31901012).

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

28887940 is a wasteful number, since it uses less digits than its factorization.

28887940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2967 (or 2965 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 46.

The square root of 28887940 is about 5374.7502267547. The cubic root of 28887940 is about 306.8354432222.

The spelling of 28887940 in words is "twenty-eight million, eight hundred eighty-seven thousand, nine hundred forty".