21632136 has 16 divisors (see below), whose sum is σ = 54080400. Its totient is φ = 7210704.

The previous prime is 21632131. The next prime is 21632137. The reversal of 21632136 is 63123612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 901339 = 21632136 / (2 + 1 + 6 + 3 + 2 + 1 + 3 + 6).

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

It is not an unprimeable number, because it can be changed into a prime (21632131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 450646 + ... + 450693.

It is an arithmetic number, because the mean of its divisors is an integer number (3380025).

Almost surely, 2^21632136 is an apocalyptic number.

It is an amenable number.

21632136 is an abundant number, since it is smaller than the sum of its proper divisors (32448264).

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

21632136 is a wasteful number, since it uses less digits than its factorization.

21632136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901348 (or 901344 counting only the distinct ones).

The product of its digits is 1296, while the sum is 24.

The square root of 21632136 is about 4651.0360136211. The cubic root of 21632136 is about 278.6333746339.

Adding to 21632136 its reverse (63123612), we get a palindrome (84755748).

The spelling of 21632136 in words is "twenty-one million, six hundred thirty-two thousand, one hundred thirty-six".