21455104 has 72 divisors (see below), whose sum is σ = 49301280. Its totient is φ = 9216000.

The previous prime is 21455101. The next prime is 21455107. The reversal of 21455104 is 40155412.

It is an interprime number because it is at equal distance from previous prime (21455101) and next prime (21455107).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (21455101) 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, 53304 + ... + 53704.

It is an arithmetic number, because the mean of its divisors is an integer number (684740).

Almost surely, 2^21455104 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 21455104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24650640).

21455104 is an abundant number, since it is smaller than the sum of its proper divisors (27846176).

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

21455104 is a wasteful number, since it uses less digits than its factorization.

21455104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 21455104 is about 4631.9654575569. The cubic root of 21455104 is about 277.8712030399.

The spelling of 21455104 in words is "twenty-one million, four hundred fifty-five thousand, one hundred four".