28413421 has 4 divisors (see below), whose sum is σ = 28694844. Its totient is φ = 28132000.

The previous prime is 28413403. The next prime is 28413431. The reversal of 28413421 is 12431482.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20376196 + 8037225 = 4514^2 + 2835^2 .

It is a cyclic number.

It is not a de Polignac number, because 28413421 - 2¹³ = 28405229 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 (28413431) 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, 140560 + ... + 140761.

It is an arithmetic number, because the mean of its divisors is an integer number (7173711).

Almost surely, 2^28413421 is an apocalyptic number.

It is an amenable number.

28413421 is a deficient number, since it is larger than the sum of its proper divisors (281423).

28413421 is a wasteful number, since it uses less digits than its factorization.

28413421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281422.

The product of its digits is 1536, while the sum is 25.

The square root of 28413421 is about 5330.4240919462. The cubic root of 28413421 is about 305.1461129179.

It can be divided in two parts, 28 and 413421, that added together give a square (413449 = 643²).

The spelling of 28413421 in words is "twenty-eight million, four hundred thirteen thousand, four hundred twenty-one".