28058018661 has 6 divisors (see below), whose sum is σ = 40528249190. Its totient is φ = 18705345768.

The previous prime is 28058018657. The next prime is 28058018699. The reversal of 28058018661 is 16681085082.

28058018661 is a `hidden beast` number, since 2 + 8 + 0 + 580 + 1 + 8 + 6 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 28057925025 + 93636 = 167505^2 + 306^2 .

It is not a de Polignac number, because 28058018661 - 2² = 28058018657 is a prime.

It is a super-2 number, since 2×28058018661² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28058008661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1558778806 + ... + 1558778823.

Almost surely, 2^28058018661 is an apocalyptic number.

It is an amenable number.

28058018661 is a deficient number, since it is larger than the sum of its proper divisors (12470230529).

28058018661 is a wasteful number, since it uses less digits than its factorization.

28058018661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3117557635 (or 3117557632 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 45.

The spelling of 28058018661 in words is "twenty-eight billion, fifty-eight million, eighteen thousand, six hundred sixty-one".