21122504 has 32 divisors (see below), whose sum is σ = 43182720. Its totient is φ = 9627456.

The previous prime is 21122473. The next prime is 21122561. The reversal of 21122504 is 40522112.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7409 + ... + 9855.

It is an arithmetic number, because the mean of its divisors is an integer number (1349460).

Almost surely, 2^21122504 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 21122504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21591360).

21122504 is an abundant number, since it is smaller than the sum of its proper divisors (22060216).

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

21122504 is a wasteful number, since it uses less digits than its factorization.

21122504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2549 (or 2545 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 21122504 is about 4595.9225406876. The cubic root of 21122504 is about 276.4278528216.

Adding to 21122504 its reverse (40522112), we get a palindrome (61644616).

The spelling of 21122504 in words is "twenty-one million, one hundred twenty-two thousand, five hundred four".