28312820401 has 4 divisors (see below), whose sum is σ = 28316549952. Its totient is φ = 28309090852.

The previous prime is 28312820383. The next prime is 28312820407. The reversal of 28312820401 is 10402821382.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10402821382 = 2 ⋅5201410691.

It is a cyclic number.

It is not a de Polignac number, because 28312820401 - 2⁹ = 28312819889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28312820407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1853365 + ... + 1868578.

It is an arithmetic number, because the mean of its divisors is an integer number (7079137488).

Almost surely, 2^28312820401 is an apocalyptic number.

It is an amenable number.

28312820401 is a deficient number, since it is larger than the sum of its proper divisors (3729551).

28312820401 is an equidigital number, since it uses as much as digits as its factorization.

28312820401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3729550.

The product of its (nonzero) digits is 6144, while the sum is 31.

The spelling of 28312820401 in words is "twenty-eight billion, three hundred twelve million, eight hundred twenty thousand, four hundred one".