668543954 has 32 divisors (see below), whose sum is σ = 1125755904. Its totient is φ = 295669440.

The previous prime is 668543951. The next prime is 668543963. The reversal of 668543954 is 459345866.

668543954 = T₂₅₂ + T₂₅₃ + ... + T₁₅₉₀.

It is not an unprimeable number, because it can be changed into a prime (668543951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78992 + ... + 87044.

It is an arithmetic number, because the mean of its divisors is an integer number (35179872).

Almost surely, 2^668543954 is an apocalyptic number.

668543954 is a deficient number, since it is larger than the sum of its proper divisors (457211950).

668543954 is a wasteful number, since it uses less digits than its factorization.

668543954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8202.

The product of its digits is 3110400, while the sum is 50.

The square root of 668543954 is about 25856.2169313301. The cubic root of 668543954 is about 874.3996770389.

The spelling of 668543954 in words is "six hundred sixty-eight million, five hundred forty-three thousand, nine hundred fifty-four".