28163721006685 has 16 divisors (see below), whose sum is σ = 38809338039360. Its totient is φ = 19404669018240.

The previous prime is 28163721006683. The next prime is 28163721006689. The reversal of 28163721006685 is 58660012736182.

It is a happy number.

It is not a de Polignac number, because 28163721006685 - 2¹ = 28163721006683 is a prime.

It is a super-3 number, since 3×28163721006685³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28163721006683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13475463552 + ... + 13475465641.

It is an arithmetic number, because the mean of its divisors is an integer number (2425583627460).

Almost surely, 2^{28163721006685} is an apocalyptic number.

It is an amenable number.

28163721006685 is a deficient number, since it is larger than the sum of its proper divisors (10645617032675).

28163721006685 is a wasteful number, since it uses less digits than its factorization.

28163721006685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26950929228.

The product of its (nonzero) digits is 5806080, while the sum is 55.

The spelling of 28163721006685 in words is "twenty-eight trillion, one hundred sixty-three billion, seven hundred twenty-one million, six thousand, six hundred eighty-five".