643254351306 has 64 divisors (see below), whose sum is σ = 1589508894720. Its totient is φ = 169408169280.

The previous prime is 643254351227. The next prime is 643254351319. The reversal of 643254351306 is 603153452346.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10863490 + ... + 10922541.

It is an arithmetic number, because the mean of its divisors is an integer number (24836076480).

Almost surely, 2^643254351306 is an apocalyptic number.

643254351306 is an abundant number, since it is smaller than the sum of its proper divisors (946254543414).

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

643254351306 is a wasteful number, since it uses less digits than its factorization.

643254351306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21786099.

The product of its (nonzero) digits is 777600, while the sum is 42.

The spelling of 643254351306 in words is "six hundred forty-three billion, two hundred fifty-four million, three hundred fifty-one thousand, three hundred six".