21201323526 has 48 divisors (see below), whose sum is σ = 48721602384. Its totient is φ = 6640008192.

The previous prime is 21201323467. The next prime is 21201323537. The reversal of 21201323526 is 62532310212.

It is a happy number.

21201323526 is a `hidden beast` number, since 2 + 1 + 2 + 0 + 132 + 3 + 526 = 666.

It is a super-2 number, since 2×21201323526² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21201323526.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 120606 + ... + 238638.

It is an arithmetic number, because the mean of its divisors is an integer number (1015033383).

Almost surely, 2^21201323526 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21201323526, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24360801192).

21201323526 is an abundant number, since it is smaller than the sum of its proper divisors (27520278858).

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

21201323526 is a wasteful number, since it uses less digits than its factorization.

21201323526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118645 (or 118642 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

Adding to 21201323526 its reverse (62532310212), we get a palindrome (83733633738).

The spelling of 21201323526 in words is "twenty-one billion, two hundred one million, three hundred twenty-three thousand, five hundred twenty-six".