28012665181 has 4 divisors (see below), whose sum is σ = 29487016000. Its totient is φ = 26538314364.

The previous prime is 28012665179. The next prime is 28012665269. The reversal of 28012665181 is 18156621082.

It is a happy number.

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 28012665181 - 2¹ = 28012665179 is a prime.

It is a super-2 number, since 2×28012665181² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28012645181) 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, 737175381 + ... + 737175418.

It is an arithmetic number, because the mean of its divisors is an integer number (7371754000).

Almost surely, 2^28012665181 is an apocalyptic number.

It is an amenable number.

28012665181 is a deficient number, since it is larger than the sum of its proper divisors (1474350819).

28012665181 is a wasteful number, since it uses less digits than its factorization.

28012665181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1474350818.

The product of its (nonzero) digits is 46080, while the sum is 40.

The spelling of 28012665181 in words is "twenty-eight billion, twelve million, six hundred sixty-five thousand, one hundred eighty-one".