21013003031 has 4 divisors (see below), whose sum is σ = 21039368952. Its totient is φ = 20986637112.

The previous prime is 21013003001. The next prime is 21013003073. The reversal of 21013003031 is 13030031012.

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 21013003031 - 2¹⁴ = 21012986647 is a prime.

It is a super-2 number, since 2×21013003031² (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 = 21013002997 and 21013003015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013003001) 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, 13181765 + ... + 13183358.

It is an arithmetic number, because the mean of its divisors is an integer number (5259842238).

Almost surely, 2^21013003031 is an apocalyptic number.

21013003031 is a deficient number, since it is larger than the sum of its proper divisors (26365921).

21013003031 is an equidigital number, since it uses as much as digits as its factorization.

21013003031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26365920.

The product of its (nonzero) digits is 54, while the sum is 14.

Adding to 21013003031 its reverse (13030031012), we get a palindrome (34043034043).

The spelling of 21013003031 in words is "twenty-one billion, thirteen million, three thousand, thirty-one".