21114636 has 12 divisors (see below), whose sum is σ = 49267512. Its totient is φ = 7038208.

The previous prime is 21114623. The next prime is 21114647. The reversal of 21114636 is 63641112.

It is a tau number, because it is divible by the number of its divisors (12).

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 879765 + ... + 879788.

It is an arithmetic number, because the mean of its divisors is an integer number (4105626).

Almost surely, 2^21114636 is an apocalyptic number.

It is an amenable number.

21114636 is an abundant number, since it is smaller than the sum of its proper divisors (28152876).

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

21114636 is a wasteful number, since it uses less digits than its factorization.

21114636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1759560 (or 1759558 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 21114636 is about 4595.0664848291. The cubic root of 21114636 is about 276.3935260131.

Adding to 21114636 its reverse (63641112), we get a palindrome (84755748).

The spelling of 21114636 in words is "twenty-one million, one hundred fourteen thousand, six hundred thirty-six".