217387106825 has 48 divisors (see below), whose sum is σ = 330401531520. Its totient is φ = 138555256320.

The previous prime is 217387106821. The next prime is 217387106887. The reversal of 217387106825 is 528601783712.

It is not a de Polignac number, because 217387106825 - 2² = 217387106821 is a prime.

It is not an unprimeable number, because it can be changed into a prime (217387106821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 440564 + ... + 793013.

It is an arithmetic number, because the mean of its divisors is an integer number (6883365240).

Almost surely, 2^217387106825 is an apocalyptic number.

217387106825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

217387106825 is a deficient number, since it is larger than the sum of its proper divisors (113014424695).

217387106825 is a wasteful number, since it uses less digits than its factorization.

217387106825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1233666 (or 1233661 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 50.

The spelling of 217387106825 in words is "two hundred seventeen billion, three hundred eighty-seven million, one hundred six thousand, eight hundred twenty-five".