28313861 has 4 divisors (see below), whose sum is σ = 28343424. Its totient is φ = 28284300.

The previous prime is 28313849. The next prime is 28313863. The reversal of 28313861 is 16831382.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16831382 = 2 ⋅8415691.

It is a cyclic number.

It is not a de Polignac number, because 28313861 - 2⁶ = 28313797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28313863) 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, 13295 + ... + 15276.

It is an arithmetic number, because the mean of its divisors is an integer number (7085856).

Almost surely, 2^28313861 is an apocalyptic number.

It is an amenable number.

28313861 is a deficient number, since it is larger than the sum of its proper divisors (29563).

28313861 is an equidigital number, since it uses as much as digits as its factorization.

28313861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29562.

The product of its digits is 6912, while the sum is 32.

The square root of 28313861 is about 5321.0770526276. The cubic root of 28313861 is about 304.7892874086.

The spelling of 28313861 in words is "twenty-eight million, three hundred thirteen thousand, eight hundred sixty-one".