1643780952 has 320 divisors, whose sum is σ = 5335925760. Its totient is φ = 468115200.

The previous prime is 1643780933. The next prime is 1643780977. The reversal of 1643780952 is 2590873461.

1643780952 is digitally balanced in base 10, because in such base it contains all the possibile digits an equal number of times.

1643780952 is strictly pandigital in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 1643780898 and 1643780907.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 9501538 + ... + 9501710.

It is an arithmetic number, because the mean of its divisors is an integer number (16674768).

It is a 2-persistent number, because it is pandigital, and so is 2⋅1643780952 = 3287561904, but 3⋅1643780952 = 4931342856 is not.

It is a vampire number, since it can be written as 17028 ⋅ 96534 (with its own digits).

Almost surely, 2^1643780952 is an apocalyptic number.

1643780952 is a gapful number since it is divisible by the number (12) 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 1643780952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2667962880).

1643780952 is an abundant number, since it is smaller than the sum of its proper divisors (3692144808).

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

1643780952 is a wasteful number, since it uses less digits than its factorization.

1643780952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 1643780952 is about 40543.5685651868. The cubic root of 1643780952 is about 1180.1792679855.

The spelling of 1643780952 in words is "one billion, six hundred forty-three million, seven hundred eighty thousand, nine hundred fifty-two".