643359331 has 16 divisors (see below), whose sum is σ = 670602240. Its totient is φ = 616749120.

The previous prime is 643359257. The next prime is 643359341. The reversal of 643359331 is 133953346.

It is a cyclic number.

It is not a de Polignac number, because 643359331 - 2¹⁷ = 643228259 is a prime.

It is a super-2 number, since 2×643359331² = 827822457569535122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643359341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 994050 + ... + 994696.

It is an arithmetic number, because the mean of its divisors is an integer number (41912640).

Almost surely, 2^643359331 is an apocalyptic number.

643359331 is a deficient number, since it is larger than the sum of its proper divisors (27242909).

643359331 is a wasteful number, since it uses less digits than its factorization.

643359331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1074.

The product of its digits is 87480, while the sum is 37.

The square root of 643359331 is about 25364.5289922758. The cubic root of 643359331 is about 863.2790495560.

The spelling of 643359331 in words is "six hundred forty-three million, three hundred fifty-nine thousand, three hundred thirty-one".