28718401 has 4 divisors (see below), whose sum is σ = 29494612. Its totient is φ = 27942192.

The previous prime is 28718387. The next prime is 28718413. The reversal of 28718401 is 10481782.

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 21298225 + 7420176 = 4615^2 + 2724^2 .

It is a cyclic number.

It is not a de Polignac number, because 28718401 - 2²¹ = 26621249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28718471) 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, 388050 + ... + 388123.

It is an arithmetic number, because the mean of its divisors is an integer number (7373653).

Almost surely, 2^28718401 is an apocalyptic number.

It is an amenable number.

28718401 is a deficient number, since it is larger than the sum of its proper divisors (776211).

28718401 is an equidigital number, since it uses as much as digits as its factorization.

28718401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 776210.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 28718401 is about 5358.9552153382. The cubic root of 28718401 is about 306.2340079946.

The spelling of 28718401 in words is "twenty-eight million, seven hundred eighteen thousand, four hundred one".