6666554 has 4 divisors (see below), whose sum is σ = 9999834. Its totient is φ = 3333276.

The previous prime is 6666551. The next prime is 6666563. The reversal of 6666554 is 4556666.

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

It can be written as a sum of positive squares in only one way, i.e., 6620329 + 46225 = 2573^2 + 215^2 .

It is an Ulam number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (6666551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1666637 + ... + 1666640.

Almost surely, 2^6666554 is an apocalyptic number.

6666554 is a deficient number, since it is larger than the sum of its proper divisors (3333280).

6666554 is a wasteful number, since it uses less digits than its factorization.

6666554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3333279.

The product of its digits is 129600, while the sum is 38.

The square root of 6666554 is about 2581.9670795732. The cubic root of 6666554 is about 188.2061455363.

The spelling of 6666554 in words is "six million, six hundred sixty-six thousand, five hundred fifty-four".