21123013023311 has 4 divisors (see below), whose sum is σ = 21804400540224. Its totient is φ = 20441625506400.

The previous prime is 21123013023293. The next prime is 21123013023349. The reversal of 21123013023311 is 11332031032112.

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

It is not a de Polignac number, because 21123013023311 - 2⁶ = 21123013023247 is a prime.

It is a super-2 number, since 2×21123013023311² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123013020311) 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, 340693758410 + ... + 340693758471.

It is an arithmetic number, because the mean of its divisors is an integer number (5451100135056).

Almost surely, 2^{21123013023311} is an apocalyptic number.

21123013023311 is a deficient number, since it is larger than the sum of its proper divisors (681387516913).

21123013023311 is an equidigital number, since it uses as much as digits as its factorization.

21123013023311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681387516912.

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 21123013023311 its reverse (11332031032112), we get a palindrome (32455044055423).

The spelling of 21123013023311 in words is "twenty-one trillion, one hundred twenty-three billion, thirteen million, twenty-three thousand, three hundred eleven".