643097970 has 24 divisors (see below), whose sum is σ = 1672054956. Its totient is φ = 171492768.

The previous prime is 643097969. The next prime is 643097971. The reversal of 643097970 is 79790346.

643097970 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 (643097969) and next prime (643097971).

It can be written as a sum of positive squares in 2 ways, for example, as 631868769 + 11229201 = 25137^2 + 3351^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (643097971) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3572677 + ... + 3572856.

Almost surely, 2^643097970 is an apocalyptic number.

643097970 is an abundant number, since it is smaller than the sum of its proper divisors (1028956986).

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

643097970 is a wasteful number, since it uses less digits than its factorization.

643097970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7145546 (or 7145543 counting only the distinct ones).

The product of its (nonzero) digits is 285768, while the sum is 45.

The square root of 643097970 is about 25359.3763724584. The cubic root of 643097970 is about 863.1621330186.

The spelling of 643097970 in words is "six hundred forty-three million, ninety-seven thousand, nine hundred seventy".