28878326401 has 4 divisors (see below), whose sum is σ = 28878683904. Its totient is φ = 28877968900.

The previous prime is 28878326387. The next prime is 28878326417. The reversal of 28878326401 is 10462387882.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 28878326401 - 2⁷ = 28878326273 is a prime.

It is a super-2 number, since 2×28878326401² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28878326201) 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, 6216 + ... + 240406.

It is an arithmetic number, because the mean of its divisors is an integer number (7219670976).

Almost surely, 2^28878326401 is an apocalyptic number.

It is an amenable number.

28878326401 is a deficient number, since it is larger than the sum of its proper divisors (357503).

28878326401 is a wasteful number, since it uses less digits than its factorization.

28878326401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357502.

The product of its (nonzero) digits is 1032192, while the sum is 49.

The spelling of 28878326401 in words is "twenty-eight billion, eight hundred seventy-eight million, three hundred twenty-six thousand, four hundred one".