1264618656 has 216 divisors, whose sum is σ = 4339651680. Its totient is φ = 361210752.

The previous prime is 1264618651. The next prime is 1264618657. The reversal of 1264618656 is 6568164621.

1264618656 is a `hidden beast` number, since 1 + 26 + 4 + 618 + 6 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (216).

It is not an unprimeable number, because it can be changed into a prime (1264618651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 379365 + ... + 382683.

It is an arithmetic number, because the mean of its divisors is an integer number (20090980).

Almost surely, 2^1264618656 is an apocalyptic number.

1264618656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1264618656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2169825840).

1264618656 is an abundant number, since it is smaller than the sum of its proper divisors (3075033024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1264618656 is an equidigital number, since it uses as much as digits as its factorization.

1264618656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3358 (or 3331 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 1264618656 is about 35561.4771346748. The cubic root of 1264618656 is about 1081.4004055709.

The spelling of 1264618656 in words is "one billion, two hundred sixty-four million, six hundred eighteen thousand, six hundred fifty-six".