216778258125 has 160 divisors (see below), whose sum is σ = 471477578880. Its totient is φ = 97018560000.

The previous prime is 216778258079. The next prime is 216778258139. The reversal of 216778258125 is 521852877612.

It is a happy number.

It is not a de Polignac number, because 216778258125 - 2⁹ = 216778257613 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 2368209 + ... + 2458041.

It is an arithmetic number, because the mean of its divisors is an integer number (2946734868).

Almost surely, 2^216778258125 is an apocalyptic number.

216778258125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

216778258125 is an abundant number, since it is smaller than the sum of its proper divisors (254699320755).

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

216778258125 is a wasteful number, since it uses less digits than its factorization.

216778258125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89886 (or 89865 counting only the distinct ones).

The product of its digits is 3763200, while the sum is 54.

The spelling of 216778258125 in words is "two hundred sixteen billion, seven hundred seventy-eight million, two hundred fifty-eight thousand, one hundred twenty-five".