643033397 has 16 divisors (see below), whose sum is σ = 698956800. Its totient is φ = 589498560.

The previous prime is 643033387. The next prime is 643033409. The reversal of 643033397 is 793330346.

It is not a de Polignac number, because 643033397 - 2²² = 638839093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643033397.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643033337) 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, 131879 + ... + 136667.

It is an arithmetic number, because the mean of its divisors is an integer number (43684800).

Almost surely, 2^643033397 is an apocalyptic number.

It is an amenable number.

643033397 is a deficient number, since it is larger than the sum of its proper divisors (55923403).

643033397 is a wasteful number, since it uses less digits than its factorization.

643033397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5036.

The product of its (nonzero) digits is 122472, while the sum is 38.

The square root of 643033397 is about 25358.1031822177. The cubic root of 643033397 is about 863.1332422240.

The spelling of 643033397 in words is "six hundred forty-three million, thirty-three thousand, three hundred ninety-seven".