1643004380 has 24 divisors (see below), whose sum is σ = 3523722048. Its totient is φ = 643218368.

The previous prime is 1643004373. The next prime is 1643004383. The reversal of 1643004380 is 834003461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643004383) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 872999 + ... + 874878.

It is an arithmetic number, because the mean of its divisors is an integer number (146821752).

Almost surely, 2^1643004380 is an apocalyptic number.

1643004380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1643004380 is an abundant number, since it is smaller than the sum of its proper divisors (1880717668).

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

1643004380 is a wasteful number, since it uses less digits than its factorization.

1643004380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1747933 (or 1747931 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 1643004380 is about 40533.9904277879. The cubic root of 1643004380 is about 1179.9933878783.

The spelling of 1643004380 in words is "one billion, six hundred forty-three million, four thousand, three hundred eighty".