1821915264 has 128 divisors (see below), whose sum is σ = 5248414080. Its totient is φ = 556646400.

The previous prime is 1821915257. The next prime is 1821915269. The reversal of 1821915264 is 4625191281.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (1821915269) 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 15 ways as a sum of consecutive naturals, for example, 752584 + ... + 755000.

It is an arithmetic number, because the mean of its divisors is an integer number (41003235).

Almost surely, 2^1821915264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1821915264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2624207040).

1821915264 is an abundant number, since it is smaller than the sum of its proper divisors (3426498816).

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

1821915264 is a wasteful number, since it uses less digits than its factorization.

1821915264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2598 (or 2586 counting only the distinct ones).

The product of its digits is 34560, while the sum is 39.

The square root of 1821915264 is about 42683.8993532690. The cubic root of 1821915264 is about 1221.3572782925.

The spelling of 1821915264 in words is "one billion, eight hundred twenty-one million, nine hundred fifteen thousand, two hundred sixty-four".