670691920 has 20 divisors (see below), whose sum is σ = 1559358900. Its totient is φ = 268276736.

The previous prime is 670691897. The next prime is 670691921. The reversal of 670691920 is 29196076.

It can be written as a sum of positive squares in 2 ways, for example, as 281971264 + 388720656 = 16792^2 + 19716^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (670691921) 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 3 ways as a sum of consecutive naturals, for example, 4191745 + ... + 4191904.

It is an arithmetic number, because the mean of its divisors is an integer number (77967945).

Almost surely, 2^670691920 is an apocalyptic number.

It is an amenable number.

670691920 is an abundant number, since it is smaller than the sum of its proper divisors (888666980).

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

670691920 is a wasteful number, since it uses less digits than its factorization.

670691920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8383662 (or 8383656 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 670691920 is about 25897.7203629972. The cubic root of 670691920 is about 875.3351293145.

The spelling of 670691920 in words is "six hundred seventy million, six hundred ninety-one thousand, nine hundred twenty".