21116916 has 24 divisors (see below), whose sum is σ = 54747840. Its totient is φ = 7038936.

The previous prime is 21116911. The next prime is 21116917. The reversal of 21116916 is 61961112.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21116916.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21116911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97656 + ... + 97871.

It is an arithmetic number, because the mean of its divisors is an integer number (2281160).

Almost surely, 2^21116916 is an apocalyptic number.

It is an amenable number.

21116916 is an abundant number, since it is smaller than the sum of its proper divisors (33630924).

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

21116916 is a wasteful number, since it uses less digits than its factorization.

21116916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195540 (or 195532 counting only the distinct ones).

The product of its digits is 648, while the sum is 27.

The square root of 21116916 is about 4595.3145702988. The cubic root of 21116916 is about 276.4034741609.

The spelling of 21116916 in words is "twenty-one million, one hundred sixteen thousand, nine hundred sixteen".