1643497120 has 24 divisors (see below), whose sum is σ = 3882762324. Its totient is φ = 657398784.

The previous prime is 1643497099. The next prime is 1643497129. The reversal of 1643497120 is 217943461.

It can be written as a sum of positive squares in 2 ways, for example, as 1502647696 + 140849424 = 38764^2 + 11868^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1643497120.

It is not an unprimeable number, because it can be changed into a prime (1643497129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5135769 + ... + 5136088.

Almost surely, 2^1643497120 is an apocalyptic number.

1643497120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1643497120 is an abundant number, since it is smaller than the sum of its proper divisors (2239265204).

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

1643497120 is a wasteful number, since it uses less digits than its factorization.

1643497120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10271872 (or 10271864 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 1643497120 is about 40540.0680808506. The cubic root of 1643497120 is about 1180.1113368087. Note that the first 3 decimals are identical.

The spelling of 1643497120 in words is "one billion, six hundred forty-three million, four hundred ninety-seven thousand, one hundred twenty".