642521142566 has 4 divisors (see below), whose sum is σ = 963781713852. Its totient is φ = 321260571282.

The previous prime is 642521142553. The next prime is 642521142569. The reversal of 642521142566 is 665241125246.

642521142566 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 is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642521142569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160630285640 + ... + 160630285643.

It is an arithmetic number, because the mean of its divisors is an integer number (240945428463).

Almost surely, 2^642521142566 is an apocalyptic number.

642521142566 is a deficient number, since it is larger than the sum of its proper divisors (321260571286).

642521142566 is a wasteful number, since it uses less digits than its factorization.

642521142566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321260571285.

The product of its digits is 691200, while the sum is 44.

The spelling of 642521142566 in words is "six hundred forty-two billion, five hundred twenty-one million, one hundred forty-two thousand, five hundred sixty-six".