28405361 has 4 divisors (see below), whose sum is σ = 29900400. Its totient is φ = 26910324.

The previous prime is 28405337. The next prime is 28405367. The reversal of 28405361 is 16350482.

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: 16350482 = 2 ⋅8175241.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28405361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28405367) 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, 747491 + ... + 747528.

It is an arithmetic number, because the mean of its divisors is an integer number (7475100).

Almost surely, 2^28405361 is an apocalyptic number.

28405361 is the 2384-th centered decagonal number.

It is an amenable number.

28405361 is a deficient number, since it is larger than the sum of its proper divisors (1495039).

28405361 is a wasteful number, since it uses less digits than its factorization.

28405361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1495038.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 28405361 is about 5329.6680009171. The cubic root of 28405361 is about 305.1172567157.

The spelling of 28405361 in words is "twenty-eight million, four hundred five thousand, three hundred sixty-one".