3128756132321 has 2 divisors, whose sum is σ = 3128756132322. Its totient is φ = 3128756132320.

The previous prime is 3128756132197. The next prime is 3128756132329. The reversal of 3128756132321 is 1232316578213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1573657347025 + 1555098785296 = 1254455^2 + 1247036^2 .

It is a cyclic number.

It is not a de Polignac number, because 3128756132321 - 2²² = 3128751938017 is a prime.

It is a super-2 number, since 2×3128756132321² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3128756132329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1564378066160 + 1564378066161.

It is an arithmetic number, because the mean of its divisors is an integer number (1564378066161).

Almost surely, 2^{3128756132321} is an apocalyptic number.

It is an amenable number.

3128756132321 is a deficient number, since it is larger than the sum of its proper divisors (1).

3128756132321 is an equidigital number, since it uses as much as digits as its factorization.

3128756132321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 44.

The spelling of 3128756132321 in words is "three trillion, one hundred twenty-eight billion, seven hundred fifty-six million, one hundred thirty-two thousand, three hundred twenty-one".