21013213031 has 8 divisors (see below), whose sum is σ = 21734722464. Its totient is φ = 20301655680.

The previous prime is 21013213019. The next prime is 21013213043. The reversal of 21013213031 is 13031231012.

It is an interprime number because it is at equal distance from previous prime (21013213019) and next prime (21013213043).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21013213031 - 2¹⁸ = 21012950887 is a prime.

It is a super-2 number, since 2×21013213031² (a number of 21 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 (21013215031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2483726 + ... + 2492171.

It is an arithmetic number, because the mean of its divisors is an integer number (2716840308).

Almost surely, 2^21013213031 is an apocalyptic number.

21013213031 is a deficient number, since it is larger than the sum of its proper divisors (721509433).

21013213031 is a wasteful number, since it uses less digits than its factorization.

21013213031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4976041.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21013213031 its reverse (13031231012), we get a palindrome (34044444043).

The spelling of 21013213031 in words is "twenty-one billion, thirteen million, two hundred thirteen thousand, thirty-one".