28697661312 has 128 divisors (see below), whose sum is σ = 79178601600. Its totient is φ = 9198336000.

The previous prime is 28697661227. The next prime is 28697661367. The reversal of 28697661312 is 21316679682.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×28697661312² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2790003 + ... + 2800269.

It is an arithmetic number, because the mean of its divisors is an integer number (618582825).

Almost surely, 2^28697661312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28697661312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39589300800).

28697661312 is an abundant number, since it is smaller than the sum of its proper divisors (50480940288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28697661312 is a wasteful number, since it uses less digits than its factorization.

28697661312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10564 (or 10552 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 51.

The spelling of 28697661312 in words is "twenty-eight billion, six hundred ninety-seven million, six hundred sixty-one thousand, three hundred twelve".