1265584855621 has 2 divisors, whose sum is σ = 1265584855622. Its totient is φ = 1265584855620.

The previous prime is 1265584855603. The next prime is 1265584855631.

It is a happy number.

1265584855621 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 855874768225 + 409710087396 = 925135^2 + 640086^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 1265584855621 - 2³⁵ = 1231225117253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1265584855631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632792427810 + 632792427811.

It is an arithmetic number, because the mean of its divisors is an integer number (632792427811).

Almost surely, 2^{1265584855621} is an apocalyptic number.

It is an amenable number.

1265584855621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265584855621 is an equidigital number, since it uses as much as digits as its factorization.

1265584855621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23040000, while the sum is 58.

The spelling of 1265584855621 in words is "one trillion, two hundred sixty-five billion, five hundred eighty-four million, eight hundred fifty-five thousand, six hundred twenty-one".