21738136 has 16 divisors (see below), whose sum is σ = 46581840. Its totient is φ = 9316320.

The previous prime is 21738133. The next prime is 21738179. The reversal of 21738136 is 63183712.

It is a junction number, because it is equal to n+sod(n) for n = 21738098 and 21738107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21738131) 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, 194035 + ... + 194146.

It is an arithmetic number, because the mean of its divisors is an integer number (2911365).

Almost surely, 2^21738136 is an apocalyptic number.

It is an amenable number.

21738136 is an abundant number, since it is smaller than the sum of its proper divisors (24843704).

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

21738136 is a wasteful number, since it uses less digits than its factorization.

21738136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388194 (or 388190 counting only the distinct ones).

The product of its digits is 6048, while the sum is 31.

The square root of 21738136 is about 4662.4173987321. The cubic root of 21738136 is about 279.0877453401.

The spelling of 21738136 in words is "twenty-one million, seven hundred thirty-eight thousand, one hundred thirty-six".