28513920 has 64 divisors (see below), whose sum is σ = 90894240. Its totient is φ = 7603200.

The previous prime is 28513897. The next prime is 28513921. The reversal of 28513920 is 2931582.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (28513921) 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, 5506 + ... + 9345.

Almost surely, 2^28513920 is an apocalyptic number.

28513920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28513920 is an abundant number, since it is smaller than the sum of its proper divisors (62380320).

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

28513920 is a wasteful number, since it uses less digits than its factorization.

28513920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14873 (or 14861 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 28513920 is about 5339.8426943123. The cubic root of 28513920 is about 305.5054594578.

The spelling of 28513920 in words is "twenty-eight million, five hundred thirteen thousand, nine hundred twenty".