28547881 has 4 divisors (see below), whose sum is σ = 28575232. Its totient is φ = 28520532.

The previous prime is 28547839. The next prime is 28547903. The reversal of 28547881 is 18874582.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28547881 - 2¹³ = 28539689 is a prime.

It is a super-2 number, since 2×28547881² = 1629963019180322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28547801) 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, 12045 + ... + 14218.

It is an arithmetic number, because the mean of its divisors is an integer number (7143808).

Almost surely, 2^28547881 is an apocalyptic number.

It is an amenable number.

28547881 is a deficient number, since it is larger than the sum of its proper divisors (27351).

28547881 is a wasteful number, since it uses less digits than its factorization.

28547881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27350.

The product of its digits is 143360, while the sum is 43.

The square root of 28547881 is about 5343.0217106053. The cubic root of 28547881 is about 305.6267002943.

The spelling of 28547881 in words is "twenty-eight million, five hundred forty-seven thousand, eight hundred eighty-one".