671657757512 has 64 divisors (see below), whose sum is σ = 1490472144000. Its totient is φ = 277633230336.

The previous prime is 671657757509. The next prime is 671657757517. The reversal of 671657757512 is 215757756176.

It is a super-2 number, since 2×671657757512² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (671657757517) 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 15 ways as a sum of consecutive naturals, for example, 1319564 + ... + 1756292.

It is an arithmetic number, because the mean of its divisors is an integer number (23288627250).

Almost surely, 2^671657757512 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 671657757512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (745236072000).

671657757512 is an abundant number, since it is smaller than the sum of its proper divisors (818814386488).

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

671657757512 is a wasteful number, since it uses less digits than its factorization.

671657757512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437718 (or 437714 counting only the distinct ones).

The product of its digits is 21609000, while the sum is 59.

The spelling of 671657757512 in words is "six hundred seventy-one billion, six hundred fifty-seven million, seven hundred fifty-seven thousand, five hundred twelve".