642021260169 has 4 divisors (see below), whose sum is σ = 856028346896. Its totient is φ = 428014173444.

The previous prime is 642021260129. The next prime is 642021260197. The reversal of 642021260169 is 961062120246.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 642021260169 - 2²⁴ = 642004482953 is a prime.

It is a super-2 number, since 2×642021260169² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642021260129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107003543359 + ... + 107003543364.

It is an arithmetic number, because the mean of its divisors is an integer number (214007086724).

Almost surely, 2^642021260169 is an apocalyptic number.

It is an amenable number.

642021260169 is a deficient number, since it is larger than the sum of its proper divisors (214007086727).

642021260169 is a wasteful number, since it uses less digits than its factorization.

642021260169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214007086726.

The product of its (nonzero) digits is 62208, while the sum is 39.

The spelling of 642021260169 in words is "six hundred forty-two billion, twenty-one million, two hundred sixty thousand, one hundred sixty-nine".