642221163790 has 32 divisors (see below), whose sum is σ = 1174951604736. Its totient is φ = 252709610400.

The previous prime is 642221163781. The next prime is 642221163791. The reversal of 642221163790 is 97361122246.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642221163791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1909092 + ... + 2220151.

It is an arithmetic number, because the mean of its divisors is an integer number (36717237648).

Almost surely, 2^642221163790 is an apocalyptic number.

642221163790 is a deficient number, since it is larger than the sum of its proper divisors (532730440946).

642221163790 is a wasteful number, since it uses less digits than its factorization.

642221163790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4129504.

The product of its (nonzero) digits is 217728, while the sum is 43.

The spelling of 642221163790 in words is "six hundred forty-two billion, two hundred twenty-one million, one hundred sixty-three thousand, seven hundred ninety".