28547508781 has 8 divisors (see below), whose sum is σ = 31148679744. Its totient is φ = 25947328320.

The previous prime is 28547508763. The next prime is 28547508887. The reversal of 28547508781 is 18780574582.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28547508781 - 2⁷ = 28547508653 is a prime.

It is a super-2 number, since 2×28547508781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28547508481) 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, 186705 + ... + 303238.

It is an arithmetic number, because the mean of its divisors is an integer number (3893584968).

Almost surely, 2^28547508781 is an apocalyptic number.

It is an amenable number.

28547508781 is a deficient number, since it is larger than the sum of its proper divisors (2601170963).

28547508781 is a wasteful number, since it uses less digits than its factorization.

28547508781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495251.

The product of its (nonzero) digits is 5017600, while the sum is 55.

The spelling of 28547508781 in words is "twenty-eight billion, five hundred forty-seven million, five hundred eight thousand, seven hundred eighty-one".