28601985825 has 144 divisors (see below), whose sum is σ = 62478282880. Its totient is φ = 12216407040.

The previous prime is 28601985821. The next prime is 28601985829. The reversal of 28601985825 is 52858910682.

It is a happy number.

28601985825 is a `hidden beast` number, since 2 + 8 + 601 + 9 + 8 + 5 + 8 + 25 = 666.

It is an interprime number because it is at equal distance from previous prime (28601985821) and next prime (28601985829).

It is not a de Polignac number, because 28601985825 - 2² = 28601985821 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28601985821) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2177979 + ... + 2191071.

Almost surely, 2^28601985825 is an apocalyptic number.

28601985825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28601985825 is an abundant number, since it is smaller than the sum of its proper divisors (33876297055).

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

28601985825 is a wasteful number, since it uses less digits than its factorization.

28601985825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13208 (or 13200 counting only the distinct ones).

The product of its (nonzero) digits is 2764800, while the sum is 54.

The spelling of 28601985825 in words is "twenty-eight billion, six hundred one million, nine hundred eighty-five thousand, eight hundred twenty-five".