21057116 has 6 divisors (see below), whose sum is σ = 36849960. Its totient is φ = 10528556.

The previous prime is 21057083. The next prime is 21057131. The reversal of 21057116 is 61175012.

It is a junction number, because it is equal to n+sod(n) for n = 21057091 and 21057100.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 2632136 + ... + 2632143.

It is an arithmetic number, because the mean of its divisors is an integer number (6141660).

Almost surely, 2^21057116 is an apocalyptic number.

It is an amenable number.

21057116 is a deficient number, since it is larger than the sum of its proper divisors (15792844).

21057116 is a wasteful number, since it uses less digits than its factorization.

21057116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5264283 (or 5264281 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 21057116 is about 4588.8033298454. The cubic root of 21057116 is about 276.1423161577.

The spelling of 21057116 in words is "twenty-one million, fifty-seven thousand, one hundred sixteen".