1264643456 has 16 divisors (see below), whose sum is σ = 2519407140. Its totient is φ = 632321664.

The previous prime is 1264643449. The next prime is 1264643467. The reversal of 1264643456 is 6543464621.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4939886 + ... + 4940141.

Almost surely, 2^1264643456 is an apocalyptic number.

1264643456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1264643456 is a deficient number, since it is larger than the sum of its proper divisors (1254763684).

1264643456 is an frugal number, since it uses more digits than its factorization.

1264643456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9880041 (or 9880029 counting only the distinct ones).

The product of its digits is 414720, while the sum is 41.

The square root of 1264643456 is about 35561.8258248926. The cubic root of 1264643456 is about 1081.4074745147.

The spelling of 1264643456 in words is "one billion, two hundred sixty-four million, six hundred forty-three thousand, four hundred fifty-six".