28878401 has 2 divisors, whose sum is σ = 28878402. Its totient is φ = 28878400.

The previous prime is 28878361. The next prime is 28878433. The reversal of 28878401 is 10487882.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27615025 + 1263376 = 5255^2 + 1124^2 .

It is a cyclic number.

It is not a de Polignac number, because 28878401 - 2¹⁰ = 28877377 is a prime.

It is not a weakly prime, because it can be changed into another prime (28878301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14439200 + 14439201.

It is an arithmetic number, because the mean of its divisors is an integer number (14439201).

Almost surely, 2^28878401 is an apocalyptic number.

It is an amenable number.

28878401 is a deficient number, since it is larger than the sum of its proper divisors (1).

28878401 is an equidigital number, since it uses as much as digits as its factorization.

28878401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 28878401 is about 5373.8627634133. The cubic root of 28878401 is about 306.8016664338.

It can be divided in two parts, 28878 and 401, that multiplied together give a triangular number (11580078 = T₄₈₁₂).

The spelling of 28878401 in words is "twenty-eight million, eight hundred seventy-eight thousand, four hundred one".