28742121216 has 288 divisors, whose sum is σ = 86727083520. Its totient is φ = 9387933696.

The previous prime is 28742121209. The next prime is 28742121259. The reversal of 28742121216 is 61212124782.

28742121216 is a `hidden beast` number, since 2 + 8 + 7 + 421 + 212 + 16 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×28742121216² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 109285501 + ... + 109285763.

Almost surely, 2^28742121216 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 28742121216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43363541760).

28742121216 is an abundant number, since it is smaller than the sum of its proper divisors (57984962304).

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

28742121216 is a wasteful number, since it uses less digits than its factorization.

28742121216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 528 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

Adding to 28742121216 its reverse (61212124782), we get a palindrome (89954245998).

The spelling of 28742121216 in words is "twenty-eight billion, seven hundred forty-two million, one hundred twenty-one thousand, two hundred sixteen".