28638161506 has 8 divisors (see below), whose sum is σ = 42997429980. Its totient is φ = 14305684848.

The previous prime is 28638161501. The next prime is 28638161507. The reversal of 28638161506 is 60516183682.

It can be written as a sum of positive squares in 2 ways, for example, as 28625594481 + 12567025 = 169191^2 + 3545^2 .

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

It is a super-3 number, since 3×28638161506³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (28638161501) 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, 6695281 + ... + 6699556.

Almost surely, 2^28638161506 is an apocalyptic number.

28638161506 is a deficient number, since it is larger than the sum of its proper divisors (14359268474).

28638161506 is a wasteful number, since it uses less digits than its factorization.

28638161506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13395908.

The product of its (nonzero) digits is 414720, while the sum is 46.

The spelling of 28638161506 in words is "twenty-eight billion, six hundred thirty-eight million, one hundred sixty-one thousand, five hundred six".