21954944 has 64 divisors (see below), whose sum is σ = 49351680. Its totient is φ = 9638400.

The previous prime is 21954941. The next prime is 21954953. The reversal of 21954944 is 44945912.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 21954898 and 21954907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21954941) 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, 43397 + ... + 43899.

It is an arithmetic number, because the mean of its divisors is an integer number (771120).

Almost surely, 2^21954944 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21954944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24675840).

21954944 is an abundant number, since it is smaller than the sum of its proper divisors (27396736).

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

21954944 is a wasteful number, since it uses less digits than its factorization.

21954944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559 (or 547 counting only the distinct ones).

The product of its digits is 51840, while the sum is 38.

The square root of 21954944 is about 4685.6103124353. The cubic root of 21954944 is about 280.0125164473.

The spelling of 21954944 in words is "twenty-one million, nine hundred fifty-four thousand, nine hundred forty-four".