643461014722 has 4 divisors (see below), whose sum is σ = 965191522086. Its totient is φ = 321730507360.

The previous prime is 643461014671. The next prime is 643461014723. The reversal of 643461014722 is 227410164346.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 459712476441 + 183748538281 = 678021^2 + 428659^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (643461014723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160865253679 + ... + 160865253682.

Almost surely, 2^643461014722 is an apocalyptic number.

643461014722 is a deficient number, since it is larger than the sum of its proper divisors (321730507364).

643461014722 is a wasteful number, since it uses less digits than its factorization.

643461014722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321730507363.

The product of its (nonzero) digits is 193536, while the sum is 40.

The spelling of 643461014722 in words is "six hundred forty-three billion, four hundred sixty-one million, fourteen thousand, seven hundred twenty-two".