1264513891 has 2 divisors, whose sum is σ = 1264513892. Its totient is φ = 1264513890.

The previous prime is 1264513879. The next prime is 1264513931. The reversal of 1264513891 is 1983154621.

It is an a-pointer prime, because the next prime (1264513931) can be obtained adding 1264513891 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1264513891 is a prime.

It is not a weakly prime, because it can be changed into another prime (1264513291) 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, 632256945 + 632256946.

It is an arithmetic number, because the mean of its divisors is an integer number (632256946).

Almost surely, 2^1264513891 is an apocalyptic number.

1264513891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1264513891 is an equidigital number, since it uses as much as digits as its factorization.

1264513891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 40.

The square root of 1264513891 is about 35560.0040916758. The cubic root of 1264513891 is about 1081.3705425389.

The spelling of 1264513891 in words is "one billion, two hundred sixty-four million, five hundred thirteen thousand, eight hundred ninety-one".