647642357122 has 4 divisors (see below), whose sum is σ = 971463535686. Its totient is φ = 323821178560.

The previous prime is 647642357051. The next prime is 647642357123. The reversal of 647642357122 is 221753246746.

647642357122 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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., 406815628041 + 240826729081 = 637821^2 + 490741^2 .

It is a Smith number, since the sum of its digits (49) 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 (647642357123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161910589279 + ... + 161910589282.

Almost surely, 2^647642357122 is an apocalyptic number.

647642357122 is a deficient number, since it is larger than the sum of its proper divisors (323821178564).

647642357122 is a wasteful number, since it uses less digits than its factorization.

647642357122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323821178563.

The product of its digits is 3386880, while the sum is 49.

The spelling of 647642357122 in words is "six hundred forty-seven billion, six hundred forty-two million, three hundred fifty-seven thousand, one hundred twenty-two".