28285921039401 has 45 divisors (see below), whose sum is σ = 44173014613959. Its totient is φ = 18036696888144.

The previous prime is 28285921039391. The next prime is 28285921039487. The reversal of 28285921039401 is 10493012958282.

The square root of 28285921039401 is 5318451.

It is a perfect power (a square), and thus also a powerful number.

28285921039401 is a `hidden beast` number, since 2 + 8 + 2 + 8 + 592 + 1 + 0 + 3 + 9 + 40 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25166727056025 + 3119193983376 = 5016645^2 + 1766124^2 .

It is not a de Polignac number, because 28285921039401 - 2⁹ = 28285921038889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28285921032401) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 1100906511 + ... + 1100932203.

Almost surely, 2^{28285921039401} is an apocalyptic number.

28285921039401 is the 5318451-st square number.

28285921039401 is the 2659226-th centered octagonal number.

It is an amenable number.

28285921039401 is a deficient number, since it is larger than the sum of its proper divisors (15887093574558).

28285921039401 is an frugal number, since it uses more digits than its factorization.

28285921039401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51444 (or 25719 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 54.

The spelling of 28285921039401 in words is "twenty-eight trillion, two hundred eighty-five billion, nine hundred twenty-one million, thirty-nine thousand, four hundred one".