28939866401 has 4 divisors (see below), whose sum is σ = 28951249152. Its totient is φ = 28928483652.

The previous prime is 28939866367. The next prime is 28939866409. The reversal of 28939866401 is 10466893982.

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.

It is a cyclic number.

It is not a de Polignac number, because 28939866401 - 2²² = 28935672097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28939866409) 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, 5687561 + ... + 5692646.

It is an arithmetic number, because the mean of its divisors is an integer number (7237812288).

Almost surely, 2^28939866401 is an apocalyptic number.

It is an amenable number.

28939866401 is a deficient number, since it is larger than the sum of its proper divisors (11382751).

28939866401 is a wasteful number, since it uses less digits than its factorization.

28939866401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11382750.

The product of its (nonzero) digits is 4478976, while the sum is 56.

The spelling of 28939866401 in words is "twenty-eight billion, nine hundred thirty-nine million, eight hundred sixty-six thousand, four hundred one".