1264005257 has 12 divisors (see below), whose sum is σ = 1292341680. Its totient is φ = 1236046680.

The previous prime is 1264005251. The next prime is 1264005269. The reversal of 1264005257 is 7525004621.

It is not a de Polignac number, because 1264005257 - 2⁴ = 1264005241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1264005251) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3818582 + ... + 3818912.

It is an arithmetic number, because the mean of its divisors is an integer number (107695140).

Almost surely, 2^1264005257 is an apocalyptic number.

It is an amenable number.

1264005257 is a deficient number, since it is larger than the sum of its proper divisors (28336423).

1264005257 is an frugal number, since it uses more digits than its factorization.

1264005257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884 (or 553 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 1264005257 is about 35552.8516015242. The cubic root of 1264005257 is about 1081.2255340917.

Adding to 1264005257 its reverse (7525004621), we get a palindrome (8789009878).

The spelling of 1264005257 in words is "one billion, two hundred sixty-four million, five thousand, two hundred fifty-seven".