643516 has 6 divisors (see below), whose sum is σ = 1126160. Its totient is φ = 321756.

The previous prime is 643507. The next prime is 643523. The reversal of 643516 is 615346.

It is a super-2 number, since 2×643516² = 828225684512, which contains 22 as substring.

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80436 + ... + 80443.

2⁶⁴³⁵¹⁶ is an apocalyptic number.

It is an amenable number.

643516 is a deficient number, since it is larger than the sum of its proper divisors (482644).

643516 is a wasteful number, since it uses less digits than its factorization.

643516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160883 (or 160881 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 643516 is about 802.1944901332. The cubic root of 643516 is about 86.3349118273.

The spelling of 643516 in words is "six hundred forty-three thousand, five hundred sixteen".