28139269 has 2 divisors, whose sum is σ = 28139270. Its totient is φ = 28139268.

The previous prime is 28139261. The next prime is 28139297. The reversal of 28139269 is 96293182.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16916769 + 11222500 = 4113^2 + 3350^2 .

It is a cyclic number.

It is not a de Polignac number, because 28139269 - 2³ = 28139261 is a prime.

It is a super-2 number, since 2×28139269² = 1583636919708722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28139261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14069634 + 14069635.

It is an arithmetic number, because the mean of its divisors is an integer number (14069635).

Almost surely, 2^28139269 is an apocalyptic number.

It is an amenable number.

28139269 is a deficient number, since it is larger than the sum of its proper divisors (1).

28139269 is an equidigital number, since it uses as much as digits as its factorization.

28139269 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 40.

The square root of 28139269 is about 5304.6459825327. The cubic root of 28139269 is about 304.1615203816.

The spelling of 28139269 in words is "twenty-eight million, one hundred thirty-nine thousand, two hundred sixty-nine".