1256322133021 has 2 divisors, whose sum is σ = 1256322133022. Its totient is φ = 1256322133020.

The previous prime is 1256322132979. The next prime is 1256322133037. The reversal of 1256322133021 is 1203312236521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 945085344025 + 311236788996 = 972155^2 + 557886^2 .

It is a cyclic number.

It is not a de Polignac number, because 1256322133021 - 2¹³ = 1256322124829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1256322133321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628161066510 + 628161066511.

It is an arithmetic number, because the mean of its divisors is an integer number (628161066511).

Almost surely, 2^{1256322133021} is an apocalyptic number.

It is an amenable number.

1256322133021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256322133021 is an equidigital number, since it uses as much as digits as its factorization.

1256322133021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 31.

Adding to 1256322133021 its reverse (1203312236521), we get a palindrome (2459634369542).

The spelling of 1256322133021 in words is "one trillion, two hundred fifty-six billion, three hundred twenty-two million, one hundred thirty-three thousand, twenty-one".