6666781954 has 16 divisors (see below), whose sum is σ = 11512194048. Its totient is φ = 2836336032.

The previous prime is 6666781949. The next prime is 6666781981. The reversal of 6666781954 is 4591876666.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1736034 + ... + 1739869.

It is an arithmetic number, because the mean of its divisors is an integer number (719512128).

Almost surely, 2^6666781954 is an apocalyptic number.

6666781954 is a deficient number, since it is larger than the sum of its proper divisors (4845412094).

6666781954 is a wasteful number, since it uses less digits than its factorization.

6666781954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3476049.

The product of its digits is 13063680, while the sum is 58.

The square root of 6666781954 is about 81650.3640775716. The cubic root of 6666781954 is about 1882.0829066530.

The spelling of 6666781954 in words is "six billion, six hundred sixty-six million, seven hundred eighty-one thousand, nine hundred fifty-four".