643045620 has 72 divisors (see below), whose sum is σ = 2094501024. Its totient is φ = 146981184.

The previous prime is 643045619. The next prime is 643045649. The reversal of 643045620 is 26540346.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 106422 + ... + 112301.

It is an arithmetic number, because the mean of its divisors is an integer number (29090292).

Almost surely, 2^643045620 is an apocalyptic number.

643045620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

643045620 is an abundant number, since it is smaller than the sum of its proper divisors (1451455404).

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

643045620 is a wasteful number, since it uses less digits than its factorization.

643045620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218749 (or 218740 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 643045620 is about 25358.3441888464. The cubic root of 643045620 is about 863.1387111006.

Adding to 643045620 its reverse (26540346), we get a palindrome (669585966).

The spelling of 643045620 in words is "six hundred forty-three million, forty-five thousand, six hundred twenty".