21220353131 has 2 divisors, whose sum is σ = 21220353132. Its totient is φ = 21220353130.

The previous prime is 21220353103. The next prime is 21220353157. The reversal of 21220353131 is 13135302212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21220353131 - 2¹⁰ = 21220352107 is a prime.

It is a super-2 number, since 2×21220353131² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21220353097 and 21220353106.

It is not a weakly prime, because it can be changed into another prime (21220353191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610176565 + 10610176566.

It is an arithmetic number, because the mean of its divisors is an integer number (10610176566).

Almost surely, 2^21220353131 is an apocalyptic number.

21220353131 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220353131 is an equidigital number, since it uses as much as digits as its factorization.

21220353131 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 23.

Adding to 21220353131 its reverse (13135302212), we get a palindrome (34355655343).

The spelling of 21220353131 in words is "twenty-one billion, two hundred twenty million, three hundred fifty-three thousand, one hundred thirty-one".