28051720 has 32 divisors (see below), whose sum is σ = 65862720. Its totient is φ = 10732480.

The previous prime is 28051711. The next prime is 28051739. The reversal of 28051720 is 2715082.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14326 + ... + 16165.

It is an arithmetic number, because the mean of its divisors is an integer number (2058210).

Almost surely, 2^28051720 is an apocalyptic number.

28051720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28051720 is an abundant number, since it is smaller than the sum of its proper divisors (37811000).

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

28051720 is a wasteful number, since it uses less digits than its factorization.

28051720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30525 (or 30521 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 28051720 is about 5296.3874480631. The cubic root of 28051720 is about 303.8457493082.

The spelling of 28051720 in words is "twenty-eight million, fifty-one thousand, seven hundred twenty".