21954880 has 112 divisors (see below), whose sum is σ = 57790080. Its totient is φ = 7907328.

The previous prime is 21954869. The next prime is 21954893. The reversal of 21954880 is 8845912.

21954880 = T₃₇₉ + T₃₈₀ + ... + T₅₇₀.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139762 + ... + 139918.

Almost surely, 2^21954880 is an apocalyptic number.

21954880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21954880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28895040).

21954880 is an abundant number, since it is smaller than the sum of its proper divisors (35835200).

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

21954880 is a wasteful number, since it uses less digits than its factorization.

21954880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 21954880 is about 4685.6034830105. The cubic root of 21954880 is about 280.0122443625.

The spelling of 21954880 in words is "twenty-one million, nine hundred fifty-four thousand, eight hundred eighty".