216878125 has 12 divisors (see below), whose sum is σ = 271084212. Its totient is φ = 173500000.

The previous prime is 216878107. The next prime is 216878131. The reversal of 216878125 is 521878612.

It can be written as a sum of positive squares in 6 ways, for example, as 164301124 + 52577001 = 12818^2 + 7251^2 .

It is not a de Polignac number, because 216878125 - 2⁵ = 216878093 is a prime.

It is a super-2 number, since 2×216878125² = 94072242207031250, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31576 + ... + 37825.

It is an arithmetic number, because the mean of its divisors is an integer number (22590351).

Almost surely, 2^216878125 is an apocalyptic number.

216878125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

216878125 is a deficient number, since it is larger than the sum of its proper divisors (54206087).

216878125 is an frugal number, since it uses more digits than its factorization.

216878125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69426 (or 69406 counting only the distinct ones).

The product of its digits is 53760, while the sum is 40.

The square root of 216878125 is about 14726.7825746155. The cubic root of 216878125 is about 600.8119793572.

The spelling of 216878125 in words is "two hundred sixteen million, eight hundred seventy-eight thousand, one hundred twenty-five".