28431846521 has 8 divisors (see below), whose sum is σ = 30738054984. Its totient is φ = 26142658560.

The previous prime is 28431846517. The next prime is 28431846557. The reversal of 28431846521 is 12564813482.

It can be written as a sum of positive squares in 4 ways, for example, as 14241080896 + 14190765625 = 119336^2 + 119125^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28431846521 - 2² = 28431846517 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28431846721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4251650 + ... + 4258331.

It is an arithmetic number, because the mean of its divisors is an integer number (3842256873).

Almost surely, 2^28431846521 is an apocalyptic number.

It is an amenable number.

28431846521 is a deficient number, since it is larger than the sum of its proper divisors (2306208463).

28431846521 is a wasteful number, since it uses less digits than its factorization.

28431846521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8510251.

The product of its digits is 368640, while the sum is 44.

The spelling of 28431846521 in words is "twenty-eight billion, four hundred thirty-one million, eight hundred forty-six thousand, five hundred twenty-one".