28166401884 has 24 divisors (see below), whose sum is σ = 66239100928. Its totient is φ = 9314872560.

The previous prime is 28166401877. The next prime is 28166401903. The reversal of 28166401884 is 48810466182.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9239422 + ... + 9242469.

Almost surely, 2^28166401884 is an apocalyptic number.

It is an amenable number.

28166401884 is an abundant number, since it is smaller than the sum of its proper divisors (38072699044).

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

28166401884 is a wasteful number, since it uses less digits than its factorization.

28166401884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18482025 (or 18482023 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 48.

The spelling of 28166401884 in words is "twenty-eight billion, one hundred sixty-six million, four hundred one thousand, eight hundred eighty-four".