102721918 has 24 divisors (see below), whose sum is σ = 168231168. Its totient is φ = 47017152.

The previous prime is 102721909. The next prime is 102721919. The reversal of 102721918 is 819127201.

It is a self number, because there is not a number n which added to its sum of digits gives 102721918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102721919) by changing a digit.

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, 41730 + ... + 44122.

It is an arithmetic number, because the mean of its divisors is an integer number (7009632).

Almost surely, 2^102721918 is an apocalyptic number.

102721918 is a deficient number, since it is larger than the sum of its proper divisors (65509250).

102721918 is a wasteful number, since it uses less digits than its factorization.

102721918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2548 (or 2535 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 102721918 is about 10135.1821887917. The cubic root of 102721918 is about 468.3325825255.

The spelling of 102721918 in words is "one hundred two million, seven hundred twenty-one thousand, nine hundred eighteen".