28618913 has 4 divisors (see below), whose sum is σ = 28652208. Its totient is φ = 28585620.

The previous prime is 28618903. The next prime is 28618937. The reversal of 28618913 is 31981682.

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 28618913 - 2¹⁰ = 28617889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28618903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15323 + ... + 17088.

It is an arithmetic number, because the mean of its divisors is an integer number (7163052).

Almost surely, 2^28618913 is an apocalyptic number.

It is an amenable number.

28618913 is a deficient number, since it is larger than the sum of its proper divisors (33295).

28618913 is an equidigital number, since it uses as much as digits as its factorization.

28618913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33294.

The product of its digits is 20736, while the sum is 38.

The square root of 28618913 is about 5349.6647558515. The cubic root of 28618913 is about 305.8799741440.

The spelling of 28618913 in words is "twenty-eight million, six hundred eighteen thousand, nine hundred thirteen".