1821916416 has 144 divisors (see below), whose sum is σ = 5055220800. Its totient is φ = 581812224.

The previous prime is 1821916399. The next prime is 1821916417. The reversal of 1821916416 is 6146191281.

It is a super-3 number, since 3×1821916416³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821916417) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3986460 + ... + 3986916.

It is an arithmetic number, because the mean of its divisors is an integer number (35105700).

Almost surely, 2^1821916416 is an apocalyptic number.

1821916416 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 1821916416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2527610400).

1821916416 is an abundant number, since it is smaller than the sum of its proper divisors (3233304384).

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

1821916416 is a wasteful number, since it uses less digits than its factorization.

1821916416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 684 (or 670 counting only the distinct ones).

The product of its digits is 20736, while the sum is 39.

The square root of 1821916416 is about 42683.9128478166. The cubic root of 1821916416 is about 1221.3575357145.

The spelling of 1821916416 in words is "one billion, eight hundred twenty-one million, nine hundred sixteen thousand, four hundred sixteen".