642701826281 has 4 divisors (see below), whose sum is σ = 642711294864. Its totient is φ = 642692357700.

The previous prime is 642701826269. The next prime is 642701826313. The reversal of 642701826281 is 182628107246.

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 a cyclic number.

It is not a de Polignac number, because 642701826281 - 2³⁰ = 641628084457 is a prime.

It is a super-2 number, since 2×642701826281² (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 (642701826181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4631735 + ... + 4768476.

It is an arithmetic number, because the mean of its divisors is an integer number (160677823716).

Almost surely, 2^642701826281 is an apocalyptic number.

It is an amenable number.

642701826281 is a deficient number, since it is larger than the sum of its proper divisors (9468583).

642701826281 is an equidigital number, since it uses as much as digits as its factorization.

642701826281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9468582.

The product of its (nonzero) digits is 516096, while the sum is 47.

The spelling of 642701826281 in words is "six hundred forty-two billion, seven hundred one million, eight hundred twenty-six thousand, two hundred eighty-one".