1643315440 has 60 divisors (see below), whose sum is σ = 4137250824. Its totient is φ = 606757632.

The previous prime is 1643315437. The next prime is 1643315449. The reversal of 1643315440 is 445133461.

It is a happy number.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643315449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 47254 + ... + 74293.

Almost surely, 2^1643315440 is an apocalyptic number.

1643315440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1643315440 is an abundant number, since it is smaller than the sum of its proper divisors (2493935384).

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

1643315440 is a wasteful number, since it uses less digits than its factorization.

1643315440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121586 (or 121567 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 1643315440 is about 40537.8272728078. The cubic root of 1643315440 is about 1180.0678501635.

The spelling of 1643315440 in words is "one billion, six hundred forty-three million, three hundred fifteen thousand, four hundred forty".