28121591634 has 8 divisors (see below), whose sum is σ = 56243183280. Its totient is φ = 9373863876.

The previous prime is 28121591633. The next prime is 28121591717. The reversal of 28121591634 is 43619512182.

It is a sphenic number, since it is the product of 3 distinct primes.

28121591634 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (28121591633) 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, 2343465964 + ... + 2343465975.

It is an arithmetic number, because the mean of its divisors is an integer number (7030397910).

Almost surely, 2^28121591634 is an apocalyptic number.

28121591634 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28121591634 is a wasteful number, since it uses less digits than its factorization.

28121591634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4686931944.

The product of its digits is 103680, while the sum is 42.

The spelling of 28121591634 in words is "twenty-eight billion, one hundred twenty-one million, five hundred ninety-one thousand, six hundred thirty-four".