21451088 has 40 divisors (see below), whose sum is σ = 44032896. Its totient is φ = 10102400.

The previous prime is 21451081. The next prime is 21451099. The reversal of 21451088 is 88015412.

It is a self number, because there is not a number n which added to its sum of digits gives 21451088.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21451081) 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, 25718 + ... + 26538.

Almost surely, 2^21451088 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 21451088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22016448).

21451088 is an abundant number, since it is smaller than the sum of its proper divisors (22581808).

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

21451088 is a wasteful number, since it uses less digits than its factorization.

21451088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923 (or 917 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 21451088 is about 4631.5319279910. The cubic root of 21451088 is about 277.8538645022.

The spelling of 21451088 in words is "twenty-one million, four hundred fifty-one thousand, eighty-eight".