667661004 has 72 divisors (see below), whose sum is σ = 1741089168. Its totient is φ = 215568000.

The previous prime is 667660999. The next prime is 667661011. The reversal of 667661004 is 400166766.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 667661004.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 333334 + ... + 335330.

It is an arithmetic number, because the mean of its divisors is an integer number (24181794).

Almost surely, 2^667661004 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 667661004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (870544584).

667661004 is an abundant number, since it is smaller than the sum of its proper divisors (1073428164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

667661004 is a wasteful number, since it uses less digits than its factorization.

667661004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2295 (or 2290 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 667661004 is about 25839.1370598942. The cubic root of 667661004 is about 874.0145658212.

It can be divided in two parts, 6676 and 61004, that multiplied together give a palindrome (407262704).

The spelling of 667661004 in words is "six hundred sixty-seven million, six hundred sixty-one thousand, four".