28421207 has 4 divisors (see below), whose sum is σ = 29917080. Its totient is φ = 26925336.

The previous prime is 28421167. The next prime is 28421209. The reversal of 28421207 is 70212482.

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

It is a cyclic number.

It is not a de Polignac number, because 28421207 - 2²⁴ = 11643991 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 (28421209) 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, 747908 + ... + 747945.

It is an arithmetic number, because the mean of its divisors is an integer number (7479270).

Almost surely, 2^28421207 is an apocalyptic number.

28421207 is a deficient number, since it is larger than the sum of its proper divisors (1495873).

28421207 is a wasteful number, since it uses less digits than its factorization.

28421207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1495872.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 28421207 is about 5331.1543778060. The cubic root of 28421207 is about 305.1739829709.

Adding to 28421207 its reverse (70212482), we get a palindrome (98633689).

The spelling of 28421207 in words is "twenty-eight million, four hundred twenty-one thousand, two hundred seven".