21345108108 has 12 divisors (see below), whose sum is σ = 49805252280. Its totient is φ = 7115036032.

The previous prime is 21345108053. The next prime is 21345108121. The reversal of 21345108108 is 80180154312.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×21345108108² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 889379493 + ... + 889379516.

It is an arithmetic number, because the mean of its divisors is an integer number (4150437690).

Almost surely, 2^21345108108 is an apocalyptic number.

It is an amenable number.

21345108108 is an abundant number, since it is smaller than the sum of its proper divisors (28460144172).

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

21345108108 is a wasteful number, since it uses less digits than its factorization.

21345108108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1778759016 (or 1778759014 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The spelling of 21345108108 in words is "twenty-one billion, three hundred forty-five million, one hundred eight thousand, one hundred eight".