28770280 has 64 divisors (see below), whose sum is σ = 80714880. Its totient is φ = 8966400.

The previous prime is 28770277. The next prime is 28770281. The reversal of 28770280 is 8207782.

It is a super-2 number, since 2×28770280² = 1655458022556800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28770281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1591 + ... + 7750.

It is an arithmetic number, because the mean of its divisors is an integer number (1261170).

Almost surely, 2^28770280 is an apocalyptic number.

28770280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28770280 is an abundant number, since it is smaller than the sum of its proper divisors (51944600).

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

28770280 is a wasteful number, since it uses less digits than its factorization.

28770280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9370 (or 9366 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 34.

The square root of 28770280 is about 5363.7934337556. The cubic root of 28770280 is about 306.4182981662.

It can be divided in two parts, 287702 and 80, that added together give a palindrome (287782).

The spelling of 28770280 in words is "twenty-eight million, seven hundred seventy thousand, two hundred eighty".