2173505678 has 4 divisors (see below), whose sum is σ = 3260258520. Its totient is φ = 1086752838.

The previous prime is 2173505657. The next prime is 2173505693. The reversal of 2173505678 is 8765053712.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 543376418 + ... + 543376421.

It is an arithmetic number, because the mean of its divisors is an integer number (815064630).

Almost surely, 2^2173505678 is an apocalyptic number.

2173505678 is a deficient number, since it is larger than the sum of its proper divisors (1086752842).

2173505678 is a wasteful number, since it uses less digits than its factorization.

2173505678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086752841.

The product of its (nonzero) digits is 352800, while the sum is 44.

The square root of 2173505678 is about 46620.8716992722. The cubic root of 2173505678 is about 1295.3493942529.

The spelling of 2173505678 in words is "two billion, one hundred seventy-three million, five hundred five thousand, six hundred seventy-eight".