1264816587851 has 2 divisors, whose sum is σ = 1264816587852. Its totient is φ = 1264816587850.

The previous prime is 1264816587847. The next prime is 1264816587901. The reversal of 1264816587851 is 1587856184621.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1264816587851 - 2² = 1264816587847 is a prime.

It is a super-2 number, since 2×1264816587851² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1264816583851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632408293925 + 632408293926.

It is an arithmetic number, because the mean of its divisors is an integer number (632408293926).

Almost surely, 2^{1264816587851} is an apocalyptic number.

1264816587851 is a deficient number, since it is larger than the sum of its proper divisors (1).

1264816587851 is an equidigital number, since it uses as much as digits as its factorization.

1264816587851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25804800, while the sum is 62.

The spelling of 1264816587851 in words is "one trillion, two hundred sixty-four billion, eight hundred sixteen million, five hundred eighty-seven thousand, eight hundred fifty-one".