28638810755381 has 4 divisors (see below), whose sum is σ = 28752909603264. Its totient is φ = 28524711907500.

The previous prime is 28638810755329. The next prime is 28638810755417. The reversal of 28638810755381 is 18355701883682.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28638810755381 - 2¹⁴ = 28638810738997 is a prime.

It is a super-2 number, since 2×28638810755381² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28638810755881) 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, 57049423565 + ... + 57049424066.

It is an arithmetic number, because the mean of its divisors is an integer number (7188227400816).

Almost surely, 2^{28638810755381} is an apocalyptic number.

It is an amenable number.

28638810755381 is a deficient number, since it is larger than the sum of its proper divisors (114098847883).

28638810755381 is a wasteful number, since it uses less digits than its factorization.

28638810755381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114098847882.

The product of its (nonzero) digits is 77414400, while the sum is 65.

The spelling of 28638810755381 in words is "twenty-eight trillion, six hundred thirty-eight billion, eight hundred ten million, seven hundred fifty-five thousand, three hundred eighty-one".