28049861 has 4 divisors (see below), whose sum is σ = 32056992. Its totient is φ = 24042732.

The previous prime is 28049849. The next prime is 28049867. The reversal of 28049861 is 16894082.

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: 16894082 = 2 ⋅8447041.

It is not a de Polignac number, because 28049861 - 2⁶ = 28049797 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 (28049867) 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, 2003555 + ... + 2003568.

It is an arithmetic number, because the mean of its divisors is an integer number (8014248).

Almost surely, 2^28049861 is an apocalyptic number.

It is an amenable number.

28049861 is a deficient number, since it is larger than the sum of its proper divisors (4007131).

28049861 is an equidigital number, since it uses as much as digits as its factorization.

28049861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4007130.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 28049861 is about 5296.2119481758. The cubic root of 28049861 is about 303.8390371621.

The spelling of 28049861 in words is "twenty-eight million, forty-nine thousand, eight hundred sixty-one".