21213545026331 has 4 divisors (see below), whose sum is σ = 24244051458672. Its totient is φ = 18183038593992.

The previous prime is 21213545026319. The next prime is 21213545026381. The reversal of 21213545026331 is 13362054531212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21213545026331 - 2²² = 21213540832027 is a prime.

It is a super-2 number, since 2×21213545026331² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213545026301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1515253216160 + ... + 1515253216173.

It is an arithmetic number, because the mean of its divisors is an integer number (6061012864668).

Almost surely, 2^{21213545026331} is an apocalyptic number.

21213545026331 is a deficient number, since it is larger than the sum of its proper divisors (3030506432341).

21213545026331 is an equidigital number, since it uses as much as digits as its factorization.

21213545026331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030506432340.

The product of its (nonzero) digits is 129600, while the sum is 38.

Adding to 21213545026331 its reverse (13362054531212), we get a palindrome (34575599557543).

The spelling of 21213545026331 in words is "twenty-one trillion, two hundred thirteen billion, five hundred forty-five million, twenty-six thousand, three hundred thirty-one".