28611913 has 4 divisors (see below), whose sum is σ = 31213008. Its totient is φ = 26010820.

The previous prime is 28611911. The next prime is 28611917. The reversal of 28611913 is 31911682.

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 not a de Polignac number, because 28611913 - 2¹ = 28611911 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28611911) 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, 1300531 + ... + 1300552.

It is an arithmetic number, because the mean of its divisors is an integer number (7803252).

Almost surely, 2^28611913 is an apocalyptic number.

It is an amenable number.

28611913 is a deficient number, since it is larger than the sum of its proper divisors (2601095).

28611913 is a wasteful number, since it uses less digits than its factorization.

28611913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2601094.

The product of its digits is 2592, while the sum is 31.

The square root of 28611913 is about 5349.0104692363. The cubic root of 28611913 is about 305.8550333596.

It can be divided in two parts, 2861 and 1913, that added together give a palindrome (4774).

The spelling of 28611913 in words is "twenty-eight million, six hundred eleven thousand, nine hundred thirteen".