21616136 has 32 divisors (see below), whose sum is σ = 43761600. Its totient is φ = 9979200.

The previous prime is 21616123. The next prime is 21616139. The reversal of 21616136 is 63161612.

It is not an unprimeable number, because it can be changed into a prime (21616139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3311 + ... + 7361.

It is an arithmetic number, because the mean of its divisors is an integer number (1367550).

Almost surely, 2^21616136 is an apocalyptic number.

It is an amenable number.

21616136 is an abundant number, since it is smaller than the sum of its proper divisors (22145464).

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

21616136 is a wasteful number, since it uses less digits than its factorization.

21616136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4109 (or 4105 counting only the distinct ones).

The product of its digits is 1296, while the sum is 26.

The square root of 21616136 is about 4649.3156485659. The cubic root of 21616136 is about 278.5646615306.

Adding to 21616136 its reverse (63161612), we get a palindrome (84777748).

The spelling of 21616136 in words is "twenty-one million, six hundred sixteen thousand, one hundred thirty-six".