21144112031 has 4 divisors (see below), whose sum is σ = 24164699472. Its totient is φ = 18123524592.

The previous prime is 21144112027. The next prime is 21144112063. The reversal of 21144112031 is 13021144112.

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 21144112031 - 2² = 21144112027 is a prime.

It is a super-2 number, since 2×21144112031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21144111994 and 21144112012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144112001) 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 3 ways as a sum of consecutive naturals, for example, 1510293710 + ... + 1510293723.

It is an arithmetic number, because the mean of its divisors is an integer number (6041174868).

Almost surely, 2^21144112031 is an apocalyptic number.

21144112031 is a deficient number, since it is larger than the sum of its proper divisors (3020587441).

21144112031 is an equidigital number, since it uses as much as digits as its factorization.

21144112031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3020587440.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21144112031 its reverse (13021144112), we get a palindrome (34165256143).

The spelling of 21144112031 in words is "twenty-one billion, one hundred forty-four million, one hundred twelve thousand, thirty-one".