641667139 has 4 divisors (see below), whose sum is σ = 642621256. Its totient is φ = 640713024.

The previous prime is 641667083. The next prime is 641667149. The reversal of 641667139 is 931766146.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 641667139 - 2²⁵ = 608112707 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 641667095 and 641667104.

It is not an unprimeable number, because it can be changed into a prime (641667149) 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 3 ways as a sum of consecutive naturals, for example, 476049 + ... + 477394.

It is an arithmetic number, because the mean of its divisors is an integer number (160655314).

Almost surely, 2^641667139 is an apocalyptic number.

641667139 is a deficient number, since it is larger than the sum of its proper divisors (954117).

641667139 is an equidigital number, since it uses as much as digits as its factorization.

641667139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954116.

The product of its digits is 163296, while the sum is 43.

The square root of 641667139 is about 25331.1495791249. The cubic root of 641667139 is about 862.5215068221.

The spelling of 641667139 in words is "six hundred forty-one million, six hundred sixty-seven thousand, one hundred thirty-nine".