642806311 has 16 divisors (see below), whose sum is σ = 741280000. Its totient is φ = 546015168.

The previous prime is 642806267. The next prime is 642806317. The reversal of 642806311 is 113608246.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 642806311 - 2¹¹ = 642804263 is a prime.

It is a super-2 number, since 2×642806311² = 826399906922857442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642806317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 568795 + ... + 569923.

It is an arithmetic number, because the mean of its divisors is an integer number (46330000).

Almost surely, 2^642806311 is an apocalyptic number.

642806311 is a deficient number, since it is larger than the sum of its proper divisors (98473689).

642806311 is a wasteful number, since it uses less digits than its factorization.

642806311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1798.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 642806311 is about 25353.6252042977. The cubic root of 642806311 is about 863.0316256497.

The spelling of 642806311 in words is "six hundred forty-two million, eight hundred six thousand, three hundred eleven".