21311025522 has 32 divisors (see below), whose sum is σ = 42776979072. Its totient is φ = 7077901824.

The previous prime is 21311025443. The next prime is 21311025523. The reversal of 21311025522 is 22552011312.

It is a junction number, because it is equal to n+sod(n) for n = 21311025492 and 21311025501.

It is not an unprimeable number, because it can be changed into a prime (21311025523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1961088 + ... + 1971924.

It is an arithmetic number, because the mean of its divisors is an integer number (1336780596).

Almost surely, 2^21311025522 is an apocalyptic number.

21311025522 is an abundant number, since it is smaller than the sum of its proper divisors (21465953550).

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

21311025522 is a wasteful number, since it uses less digits than its factorization.

21311025522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12002.

The product of its (nonzero) digits is 1200, while the sum is 24.

Adding to 21311025522 its reverse (22552011312), we get a palindrome (43863036834).

The spelling of 21311025522 in words is "twenty-one billion, three hundred eleven million, twenty-five thousand, five hundred twenty-two".