21258116 has 12 divisors (see below), whose sum is σ = 40583760. Its totient is φ = 9662760.

The previous prime is 21258101. The next prime is 21258121. The reversal of 21258116 is 61185212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 241526 + ... + 241613.

It is an arithmetic number, because the mean of its divisors is an integer number (3381980).

Almost surely, 2^21258116 is an apocalyptic number.

It is an amenable number.

21258116 is a deficient number, since it is larger than the sum of its proper divisors (19325644).

21258116 is a wasteful number, since it uses less digits than its factorization.

21258116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 483154 (or 483152 counting only the distinct ones).

The product of its digits is 960, while the sum is 26.

The square root of 21258116 is about 4610.6524484068. The cubic root of 21258116 is about 277.0181709897.

The spelling of 21258116 in words is "twenty-one million, two hundred fifty-eight thousand, one hundred sixteen".