1641217678 has 4 divisors (see below), whose sum is σ = 2461826520. Its totient is φ = 820608838.

The previous prime is 1641217673. The next prime is 1641217703. The reversal of 1641217678 is 8767121461.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1641217673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410304418 + ... + 410304421.

It is an arithmetic number, because the mean of its divisors is an integer number (615456630).

Almost surely, 2^1641217678 is an apocalyptic number.

1641217678 is a deficient number, since it is larger than the sum of its proper divisors (820608842).

1641217678 is an equidigital number, since it uses as much as digits as its factorization.

1641217678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820608841.

The product of its digits is 112896, while the sum is 43.

The square root of 1641217678 is about 40511.9448804917. The cubic root of 1641217678 is about 1179.5655007581.

The spelling of 1641217678 in words is "one billion, six hundred forty-one million, two hundred seventeen thousand, six hundred seventy-eight".