671670640 has 40 divisors (see below), whose sum is σ = 1581416640. Its totient is φ = 265264896.

The previous prime is 671670631. The next prime is 671670661. The reversal of 671670640 is 46076176.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×671670640² = 902282897276019200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 671670640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46819 + ... + 59458.

It is an arithmetic number, because the mean of its divisors is an integer number (39535416).

Almost surely, 2^671670640 is an apocalyptic number.

It is an amenable number.

671670640 is an abundant number, since it is smaller than the sum of its proper divisors (909746000).

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

671670640 is a wasteful number, since it uses less digits than its factorization.

671670640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106369 (or 106363 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 671670640 is about 25916.6093461317. The cubic root of 671670640 is about 875.7607055427.

The spelling of 671670640 in words is "six hundred seventy-one million, six hundred seventy thousand, six hundred forty".