28146778836 has 48 divisors (see below), whose sum is σ = 73312555008. Its totient is φ = 8330968800.

The previous prime is 28146778823. The next prime is 28146778871. The reversal of 28146778836 is 63887764182.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 28146778836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2473780 + ... + 2485131.

It is an arithmetic number, because the mean of its divisors is an integer number (1527344896).

Almost surely, 2^28146778836 is an apocalyptic number.

It is an amenable number.

28146778836 is an abundant number, since it is smaller than the sum of its proper divisors (45165776172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28146778836 is a wasteful number, since it uses less digits than its factorization.

28146778836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4958972 (or 4958970 counting only the distinct ones).

The product of its digits is 21676032, while the sum is 60.

The spelling of 28146778836 in words is "twenty-eight billion, one hundred forty-six million, seven hundred seventy-eight thousand, eight hundred thirty-six".