28723658885 has 8 divisors (see below), whose sum is σ = 35399969016. Its totient is φ = 22357874880.

The previous prime is 28723658807. The next prime is 28723658891. The reversal of 28723658885 is 58885632782.

It can be written as a sum of positive squares in 4 ways, for example, as 16372226116 + 12351432769 = 127954^2 + 111137^2 .

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

It is not a de Polignac number, because 28723658885 - 2¹⁴ = 28723642501 is a prime.

It is a Duffinian number.

It is a Curzon 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, 77631326 + ... + 77631695.

It is an arithmetic number, because the mean of its divisors is an integer number (4424996127).

Almost surely, 2^28723658885 is an apocalyptic number.

It is an amenable number.

28723658885 is a deficient number, since it is larger than the sum of its proper divisors (6676310131).

28723658885 is a wasteful number, since it uses less digits than its factorization.

28723658885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155263063.

The product of its digits is 51609600, while the sum is 62.

The spelling of 28723658885 in words is "twenty-eight billion, seven hundred twenty-three million, six hundred fifty-eight thousand, eight hundred eighty-five".