28628171731 has 4 divisors (see below), whose sum is σ = 29326419864. Its totient is φ = 27929923600.

The previous prime is 28628171687. The next prime is 28628171779. The reversal of 28628171731 is 13717182682.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28628171731 - 2¹⁵ = 28628138963 is a prime.

It is a super-2 number, since 2×28628171731² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28628172731) 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, 349124005 + ... + 349124086.

It is an arithmetic number, because the mean of its divisors is an integer number (7331604966).

Almost surely, 2^28628171731 is an apocalyptic number.

28628171731 is a deficient number, since it is larger than the sum of its proper divisors (698248133).

28628171731 is an equidigital number, since it uses as much as digits as its factorization.

28628171731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698248132.

The product of its digits is 225792, while the sum is 46.

The spelling of 28628171731 in words is "twenty-eight billion, six hundred twenty-eight million, one hundred seventy-one thousand, seven hundred thirty-one".