667172878 has 16 divisors (see below), whose sum is σ = 1059261840. Its totient is φ = 314280000.

The previous prime is 667172843. The next prime is 667172879. The reversal of 667172878 is 878271766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667172879) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 41623 + ... + 55378.

It is an arithmetic number, because the mean of its divisors is an integer number (66203865).

Almost surely, 2^667172878 is an apocalyptic number.

667172878 is a deficient number, since it is larger than the sum of its proper divisors (392088962).

667172878 is a wasteful number, since it uses less digits than its factorization.

667172878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97203.

The product of its digits is 1580544, while the sum is 52.

The square root of 667172878 is about 25829.6898548937. The cubic root of 667172878 is about 873.8015169621.

The spelling of 667172878 in words is "six hundred sixty-seven million, one hundred seventy-two thousand, eight hundred seventy-eight".