28207538401 has 9 divisors (see below), whose sum is σ = 32814218451. Its totient is φ = 24176882352.

The previous prime is 28207538369. The next prime is 28207538413. The reversal of 28207538401 is 10483570282.

It is a happy number.

The square root of 28207538401 is 167951.

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

It can be written as a sum of positive squares in only one way, i.e., 58752225 + 28148786176 = 7665^2 + 167776^2 .

It is not a de Polignac number, because 28207538401 - 2⁵ = 28207538369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28207538441) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1163661 + ... + 1187653.

Almost surely, 2^28207538401 is an apocalyptic number.

28207538401 is the 167951-st square number.

28207538401 is the 83976-th centered octagonal number.

It is an amenable number.

28207538401 is a deficient number, since it is larger than the sum of its proper divisors (4606680050).

28207538401 is an frugal number, since it uses more digits than its factorization.

28207538401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48000 (or 24000 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 40.

The spelling of 28207538401 in words is "twenty-eight billion, two hundred seven million, five hundred thirty-eight thousand, four hundred one".