2131123333621 has 2 divisors, whose sum is σ = 2131123333622. Its totient is φ = 2131123333620.

The previous prime is 2131123333609. The next prime is 2131123333663. The reversal of 2131123333621 is 1263333211312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2131103628900 + 19704721 = 1459830^2 + 4439^2 .

It is a cyclic number.

It is not a de Polignac number, because 2131123333621 - 2⁹ = 2131123333109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2131123334621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1065561666810 + 1065561666811.

It is an arithmetic number, because the mean of its divisors is an integer number (1065561666811).

Almost surely, 2^{2131123333621} is an apocalyptic number.

It is an amenable number.

2131123333621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2131123333621 is an equidigital number, since it uses as much as digits as its factorization.

2131123333621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 31.

Adding to 2131123333621 its reverse (1263333211312), we get a palindrome (3394456544933).

The spelling of 2131123333621 in words is "two trillion, one hundred thirty-one billion, one hundred twenty-three million, three hundred thirty-three thousand, six hundred twenty-one".