1321616785057 has 2 divisors, whose sum is σ = 1321616785058. Its totient is φ = 1321616785056.

The previous prime is 1321616785037. The next prime is 1321616785067. The reversal of 1321616785057 is 7505876161231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1185030365281 + 136586419776 = 1088591^2 + 369576^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321616785057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1321616784995 and 1321616785013.

It is not a weakly prime, because it can be changed into another prime (1321616785037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660808392528 + 660808392529.

It is an arithmetic number, because the mean of its divisors is an integer number (660808392529).

Almost surely, 2^{1321616785057} is an apocalyptic number.

It is an amenable number.

1321616785057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321616785057 is an equidigital number, since it uses as much as digits as its factorization.

1321616785057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2116800, while the sum is 52.

The spelling of 1321616785057 in words is "one trillion, three hundred twenty-one billion, six hundred sixteen million, seven hundred eighty-five thousand, fifty-seven".