28386820531 has 4 divisors (see below), whose sum is σ = 29046979192. Its totient is φ = 27726661872.

The previous prime is 28386820489. The next prime is 28386820543. The reversal of 28386820531 is 13502868382.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28386820531 - 2¹⁵ = 28386787763 is a prime.

It is a super-2 number, since 2×28386820531² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28386821531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 330079266 + ... + 330079351.

It is an arithmetic number, because the mean of its divisors is an integer number (7261744798).

Almost surely, 2^28386820531 is an apocalyptic number.

28386820531 is a deficient number, since it is larger than the sum of its proper divisors (660158661).

28386820531 is an equidigital number, since it uses as much as digits as its factorization.

28386820531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660158660.

The product of its (nonzero) digits is 552960, while the sum is 46.

The spelling of 28386820531 in words is "twenty-eight billion, three hundred eighty-six million, eight hundred twenty thousand, five hundred thirty-one".