28993421778916 has 27 divisors (see below), whose sum is σ = 59022476367267. Its totient is φ = 12425719883640.

The previous prime is 28993421778913. The next prime is 28993421778967. The reversal of 28993421778916 is 61987712439982.

The square root of 28993421778916 is 5384554.

It is a perfect power (a square), and thus also a powerful number.

It is not an unprimeable number, because it can be changed into a prime (28993421778913) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 75191451 + ... + 75576061.

Almost surely, 2^{28993421778916} is an apocalyptic number.

28993421778916 is the 5384554-th square number.

It is an amenable number.

28993421778916 is an abundant number, since it is smaller than the sum of its proper divisors (30029054588351).

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

28993421778916 is an frugal number, since it uses more digits than its factorization.

28993421778916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769240 (or 384620 counting only the distinct ones).

The product of its digits is 658409472, while the sum is 76.

The spelling of 28993421778916 in words is "twenty-eight trillion, nine hundred ninety-three billion, four hundred twenty-one million, seven hundred seventy-eight thousand, nine hundred sixteen".