21938046 has 64 divisors (see below), whose sum is σ = 50561280. Its totient is φ = 6289920.

The previous prime is 21938039. The next prime is 21938057. The reversal of 21938046 is 64083912.

It is a junction number, because it is equal to n+sod(n) for n = 21937998 and 21938016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 167401 + ... + 167531.

It is an arithmetic number, because the mean of its divisors is an integer number (790020).

Almost surely, 2^21938046 is an apocalyptic number.

21938046 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21938046, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25280640).

21938046 is an abundant number, since it is smaller than the sum of its proper divisors (28623234).

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

21938046 is a wasteful number, since it uses less digits than its factorization.

21938046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 21938046 is about 4683.8067850841. The cubic root of 21938046 is about 279.9406591934.

The spelling of 21938046 in words is "twenty-one million, nine hundred thirty-eight thousand, forty-six".