21203103131 has 4 divisors (see below), whose sum is σ = 24232117872. Its totient is φ = 18174088392.

The previous prime is 21203103113. The next prime is 21203103133. The reversal of 21203103131 is 13130130212.

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 21203103131 - 2¹⁴ = 21203086747 is a prime.

It is a super-2 number, since 2×21203103131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21203103133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1514507360 + ... + 1514507373.

It is an arithmetic number, because the mean of its divisors is an integer number (6058029468).

Almost surely, 2^21203103131 is an apocalyptic number.

21203103131 is a deficient number, since it is larger than the sum of its proper divisors (3029014741).

21203103131 is an equidigital number, since it uses as much as digits as its factorization.

21203103131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3029014740.

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

Adding to 21203103131 its reverse (13130130212), we get a palindrome (34333233343).

The spelling of 21203103131 in words is "twenty-one billion, two hundred three million, one hundred three thousand, one hundred thirty-one".