21203202131 has 2 divisors, whose sum is σ = 21203202132. Its totient is φ = 21203202130.

The previous prime is 21203202067. The next prime is 21203202169. The reversal of 21203202131 is 13120230212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21203202131 - 2⁶ = 21203202067 is a prime.

It is a super-3 number, since 3×21203202131³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (21203202431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601601065 + 10601601066.

It is an arithmetic number, because the mean of its divisors is an integer number (10601601066).

Almost surely, 2^21203202131 is an apocalyptic number.

21203202131 is a deficient number, since it is larger than the sum of its proper divisors (1).

21203202131 is an equidigital number, since it uses as much as digits as its factorization.

21203202131 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21203202131 its reverse (13120230212), we get a palindrome (34323432343).

The spelling of 21203202131 in words is "twenty-one billion, two hundred three million, two hundred two thousand, one hundred thirty-one".