21738654 has 60 divisors (see below), whose sum is σ = 55056456. Its totient is φ = 6198696.

The previous prime is 21738637. The next prime is 21738659. The reversal of 21738654 is 45683712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21738659) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 42967 + ... + 43469.

Almost surely, 2^21738654 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21738654, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27528228).

21738654 is an abundant number, since it is smaller than the sum of its proper divisors (33317802).

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

21738654 is an equidigital number, since it uses as much as digits as its factorization.

21738654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539 (or 515 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 21738654 is about 4662.4729489832. The cubic root of 21738654 is about 279.0899621248.

The spelling of 21738654 in words is "twenty-one million, seven hundred thirty-eight thousand, six hundred fifty-four".