21145108 has 6 divisors (see below), whose sum is σ = 37003946. Its totient is φ = 10572552.

The previous prime is 21145079. The next prime is 21145109. The reversal of 21145108 is 80154112.

It can be written as a sum of positive squares in only one way, i.e., 20088324 + 1056784 = 4482^2 + 1028^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21145109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2643135 + ... + 2643142.

Almost surely, 2^21145108 is an apocalyptic number.

It is an amenable number.

21145108 is a deficient number, since it is larger than the sum of its proper divisors (15858838).

21145108 is a wasteful number, since it uses less digits than its factorization.

21145108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5286281 (or 5286279 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 22.

The square root of 21145108 is about 4598.3810194459. The cubic root of 21145108 is about 276.5264230106.

The spelling of 21145108 in words is "twenty-one million, one hundred forty-five thousand, one hundred eight".