21116412 has 18 divisors (see below), whose sum is σ = 53377688. Its totient is φ = 7038792.

The previous prime is 21116411. The next prime is 21116453. The reversal of 21116412 is 21461112.

21116412 is a `hidden beast` number, since 21 + 1 + 1 + 641 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21116411) 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 5 ways as a sum of consecutive naturals, for example, 293248 + ... + 293319.

Almost surely, 2^21116412 is an apocalyptic number.

It is an amenable number.

21116412 is an abundant number, since it is smaller than the sum of its proper divisors (32261276).

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

21116412 is a wasteful number, since it uses less digits than its factorization.

21116412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586577 (or 586572 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 21116412 is about 4595.2597315059. The cubic root of 21116412 is about 276.4012751583.

Adding to 21116412 its reverse (21461112), we get a palindrome (42577524).

It can be divided in two parts, 21116 and 412, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 21116412 in words is "twenty-one million, one hundred sixteen thousand, four hundred twelve".