1264393957 has 4 divisors (see below), whose sum is σ = 1295232876. Its totient is φ = 1233555040.

The previous prime is 1264393937. The next prime is 1264393967. The reversal of 1264393957 is 7593934621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 373610241 + 890783716 = 19329^2 + 29846^2 .

It is a cyclic number.

It is not a de Polignac number, because 1264393957 - 2²³ = 1256005349 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1264393957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1264393937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15419398 + ... + 15419479.

It is an arithmetic number, because the mean of its divisors is an integer number (323808219).

Almost surely, 2^1264393957 is an apocalyptic number.

It is an amenable number.

1264393957 is a deficient number, since it is larger than the sum of its proper divisors (30838919).

1264393957 is an equidigital number, since it uses as much as digits as its factorization.

1264393957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30838918.

The product of its digits is 1224720, while the sum is 49.

The square root of 1264393957 is about 35558.3176908020. The cubic root of 1264393957 is about 1081.3363535919.

The spelling of 1264393957 in words is "one billion, two hundred sixty-four million, three hundred ninety-three thousand, nine hundred fifty-seven".