1264155869 has 2 divisors, whose sum is σ = 1264155870. Its totient is φ = 1264155868.

The previous prime is 1264155863. The next prime is 1264155917. The reversal of 1264155869 is 9685514621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 799192900 + 464962969 = 28270^2 + 21563^2 .

It is an emirp because it is prime and its reverse (9685514621) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1264155869 is a prime.

It is a super-2 number, since 2×1264155869² = 3196180122254290322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1264155863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632077934 + 632077935.

It is an arithmetic number, because the mean of its divisors is an integer number (632077935).

Almost surely, 2^1264155869 is an apocalyptic number.

It is an amenable number.

1264155869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1264155869 is an equidigital number, since it uses as much as digits as its factorization.

1264155869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 518400, while the sum is 47.

The square root of 1264155869 is about 35554.9696807633. The cubic root of 1264155869 is about 1081.2684767065.

The spelling of 1264155869 in words is "one billion, two hundred sixty-four million, one hundred fifty-five thousand, eight hundred sixty-nine".