642842668515 has 16 divisors (see below), whose sum is σ = 1029055742208. Its totient is φ = 342680265696.

The previous prime is 642842668499. The next prime is 642842668519. The reversal of 642842668515 is 515866248246.

It is not a de Polignac number, because 642842668515 - 2⁴ = 642842668499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (642842668519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10540927 + ... + 10601736.

It is an arithmetic number, because the mean of its divisors is an integer number (64315983888).

Almost surely, 2^642842668515 is an apocalyptic number.

642842668515 is a deficient number, since it is larger than the sum of its proper divisors (386213073693).

642842668515 is a wasteful number, since it uses less digits than its factorization.

642842668515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21144698.

The product of its digits is 22118400, while the sum is 57.

The spelling of 642842668515 in words is "six hundred forty-two billion, eight hundred forty-two million, six hundred sixty-eight thousand, five hundred fifteen".