643437494 has 8 divisors (see below), whose sum is σ = 1103035728. Its totient is φ = 275758920.

The previous prime is 643437467. The next prime is 643437521. The reversal of 643437494 is 494734346.

643437494 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (643437467) and next prime (643437521).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22979897 + ... + 22979924.

It is an arithmetic number, because the mean of its divisors is an integer number (137879466).

Almost surely, 2^643437494 is an apocalyptic number.

643437494 is a deficient number, since it is larger than the sum of its proper divisors (459598234).

643437494 is a wasteful number, since it uses less digits than its factorization.

643437494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45959830.

The product of its digits is 870912, while the sum is 44.

The square root of 643437494 is about 25366.0697389249. The cubic root of 643437494 is about 863.3140086344.

The spelling of 643437494 in words is "six hundred forty-three million, four hundred thirty-seven thousand, four hundred ninety-four".