1264616861 has 2 divisors, whose sum is σ = 1264616862. Its totient is φ = 1264616860.

The previous prime is 1264616849. The next prime is 1264616909. The reversal of 1264616861 is 1686164621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1142845636 + 121771225 = 33806^2 + 11035^2 .

It is a cyclic number.

It is not a de Polignac number, because 1264616861 - 2¹⁰ = 1264615837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1264616831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632308430 + 632308431.

It is an arithmetic number, because the mean of its divisors is an integer number (632308431).

Almost surely, 2^1264616861 is an apocalyptic number.

It is an amenable number.

1264616861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1264616861 is an equidigital number, since it uses as much as digits as its factorization.

1264616861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 41.

The square root of 1264616861 is about 35561.4518966816. The cubic root of 1264616861 is about 1081.3998939240.

The spelling of 1264616861 in words is "one billion, two hundred sixty-four million, six hundred sixteen thousand, eight hundred sixty-one".