667291128 has 64 divisors (see below), whose sum is σ = 1908576000. Its totient is φ = 190451712.

The previous prime is 667291091. The next prime is 667291169. The reversal of 667291128 is 821192766.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 667291128.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235303 + ... + 238121.

It is an arithmetic number, because the mean of its divisors is an integer number (29821500).

Almost surely, 2^667291128 is an apocalyptic number.

It is an amenable number.

667291128 is an abundant number, since it is smaller than the sum of its proper divisors (1241284872).

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

667291128 is a wasteful number, since it uses less digits than its factorization.

667291128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4244 (or 4240 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 667291128 is about 25831.9787859931. The cubic root of 667291128 is about 873.8531382279.

The spelling of 667291128 in words is "six hundred sixty-seven million, two hundred ninety-one thousand, one hundred twenty-eight".