216809998725 has 12 divisors (see below), whose sum is σ = 358459198016. Its totient is φ = 115631999280.

The previous prime is 216809998703. The next prime is 216809998747. The reversal of 216809998725 is 527899908612.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (216809998703) and next prime (216809998747).

It is not a de Polignac number, because 216809998725 - 2⁹ = 216809998213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1445399917 + ... + 1445400066.

Almost surely, 2^216809998725 is an apocalyptic number.

216809998725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

216809998725 is a deficient number, since it is larger than the sum of its proper divisors (141649199291).

216809998725 is a wasteful number, since it uses less digits than its factorization.

216809998725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2890799996 (or 2890799991 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 66.

The spelling of 216809998725 in words is "two hundred sixteen billion, eight hundred nine million, nine hundred ninety-eight thousand, seven hundred twenty-five".