642262017081 has 4 divisors (see below), whose sum is σ = 856349356112. Its totient is φ = 428174678052.

The previous prime is 642262017049. The next prime is 642262017091. The reversal of 642262017081 is 180710262246.

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 642262017081 - 2⁵ = 642262017049 is a prime.

It is a super-2 number, since 2×642262017081² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (642262017091) 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, 107043669511 + ... + 107043669516.

It is an arithmetic number, because the mean of its divisors is an integer number (214087339028).

Almost surely, 2^642262017081 is an apocalyptic number.

It is an amenable number.

642262017081 is a deficient number, since it is larger than the sum of its proper divisors (214087339031).

642262017081 is a wasteful number, since it uses less digits than its factorization.

642262017081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214087339030.

The product of its (nonzero) digits is 64512, while the sum is 39.

The spelling of 642262017081 in words is "six hundred forty-two billion, two hundred sixty-two million, seventeen thousand, eighty-one".