21126300521 has 16 divisors (see below), whose sum is σ = 21698002944. Its totient is φ = 20563974144.

The previous prime is 21126300511. The next prime is 21126300523. The reversal of 21126300521 is 12500362112.

It is a cyclic number.

It is not a de Polignac number, because 21126300521 - 2⁶ = 21126300457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21126300523) 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, 1783400 + ... + 1795206.

It is an arithmetic number, because the mean of its divisors is an integer number (1356125184).

Almost surely, 2^21126300521 is an apocalyptic number.

It is an amenable number.

21126300521 is a deficient number, since it is larger than the sum of its proper divisors (571702423).

21126300521 is a wasteful number, since it uses less digits than its factorization.

21126300521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12200.

The product of its (nonzero) digits is 720, while the sum is 23.

Adding to 21126300521 its reverse (12500362112), we get a palindrome (33626662633).

The spelling of 21126300521 in words is "twenty-one billion, one hundred twenty-six million, three hundred thousand, five hundred twenty-one".