6639856154 has 8 divisors (see below), whose sum is σ = 10392818400. Its totient is φ = 3175583356.

The previous prime is 6639856121. The next prime is 6639856163. The reversal of 6639856154 is 4516589366.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6639856096 and 6639856105.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72172304 + ... + 72172395.

It is an arithmetic number, because the mean of its divisors is an integer number (1299102300).

Almost surely, 2^6639856154 is an apocalyptic number.

6639856154 is a deficient number, since it is larger than the sum of its proper divisors (3752962246).

6639856154 is a wasteful number, since it uses less digits than its factorization.

6639856154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144344724.

The product of its digits is 4665600, while the sum is 53.

The square root of 6639856154 is about 81485.3125047698. The cubic root of 6639856154 is about 1879.5457022478.

The spelling of 6639856154 in words is "six billion, six hundred thirty-nine million, eight hundred fifty-six thousand, one hundred fifty-four".