28724025 has 48 divisors (see below), whose sum is σ = 53264448. Its totient is φ = 13536000.

The previous prime is 28724009. The next prime is 28724027. The reversal of 28724025 is 52042782.

It is not a de Polignac number, because 28724025 - 2⁴ = 28724009 is a prime.

It is a super-2 number, since 2×28724025² = 1650139224401250, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28723983 and 28724001.

It is not an unprimeable number, because it can be changed into a prime (28724027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 30055 + ... + 30995.

It is an arithmetic number, because the mean of its divisors is an integer number (1109676).

Almost surely, 2^28724025 is an apocalyptic number.

28724025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28724025 is a deficient number, since it is larger than the sum of its proper divisors (24540423).

28724025 is a wasteful number, since it uses less digits than its factorization.

28724025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002 (or 997 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 30.

The square root of 28724025 is about 5359.4799187981. The cubic root of 28724025 is about 306.2539968936.

The spelling of 28724025 in words is "twenty-eight million, seven hundred twenty-four thousand, twenty-five".