28180780 has 24 divisors (see below), whose sum is σ = 60152400. Its totient is φ = 11087040.

The previous prime is 28180771. The next prime is 28180783. The reversal of 28180780 is 8708182.

It is a super-2 number, since 2×28180780² = 1588312722816800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28180783) 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, 10330 + ... + 12769.

It is an arithmetic number, because the mean of its divisors is an integer number (2506350).

Almost surely, 2^28180780 is an apocalyptic number.

28180780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28180780 is an abundant number, since it is smaller than the sum of its proper divisors (31971620).

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

28180780 is a wasteful number, since it uses less digits than its factorization.

28180780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23169 (or 23167 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 28180780 is about 5308.5572427921. The cubic root of 28180780 is about 304.3110130747.

The spelling of 28180780 in words is "twenty-eight million, one hundred eighty thousand, seven hundred eighty".