28113720 has 32 divisors (see below), whose sum is σ = 84341520. Its totient is φ = 7496960.

The previous prime is 28113719. The next prime is 28113727. The reversal of 28113720 is 2731182.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28113727) 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, 117021 + ... + 117260.

Almost surely, 2^28113720 is an apocalyptic number.

28113720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28113720 is an abundant number, since it is smaller than the sum of its proper divisors (56227800).

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

28113720 is a wasteful number, since it uses less digits than its factorization.

28113720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234295 (or 234291 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 28113720 is about 5302.2372636464. The cubic root of 28113720 is about 304.0694382008.

The spelling of 28113720 in words is "twenty-eight million, one hundred thirteen thousand, seven hundred twenty".