1264100640 has 192 divisors, whose sum is σ = 4484616192. Its totient is φ = 296524800.

The previous prime is 1264100587. The next prime is 1264100641. The reversal of 1264100640 is 460014621.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 1264100640.

It is not an unprimeable number, because it can be changed into a prime (1264100641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 159819 + ... + 167541.

It is an arithmetic number, because the mean of its divisors is an integer number (23357376).

Almost surely, 2^1264100640 is an apocalyptic number.

1264100640 is a gapful number since it is divisible by the number (10) 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 1264100640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2242308096).

1264100640 is an abundant number, since it is smaller than the sum of its proper divisors (3220515552).

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

1264100640 is a wasteful number, since it uses less digits than its factorization.

1264100640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7783 (or 7775 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 1264100640 is about 35554.1930016700. The cubic root of 1264100640 is about 1081.2527301656.

The spelling of 1264100640 in words is "one billion, two hundred sixty-four million, one hundred thousand, six hundred forty".