671442581056 has 63 divisors (see below), whose sum is σ = 1442952834561. Its totient is φ = 309857243904.

The previous prime is 671442580981. The next prime is 671442581057. The reversal of 671442581056 is 650185244176.

The square root of 671442581056 is 819416.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 99325825600 + 572116755456 = 315160^2 + 756384^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671442581057) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 85215325 + ... + 85223203.

It is an arithmetic number, because the mean of its divisors is an integer number (22904013247).

Almost surely, 2^671442581056 is an apocalyptic number.

671442581056 is the 819416-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 671442581056

671442581056 is an abundant number, since it is smaller than the sum of its proper divisors (771510253505).

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

671442581056 is an frugal number, since it uses more digits than its factorization.

671442581056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15796 (or 7894 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 49.

Multiplying 671442581056 by its sum of digits (49), we get a square (32900686471744 = 5735912²).

The spelling of 671442581056 in words is "six hundred seventy-one billion, four hundred forty-two million, five hundred eighty-one thousand, fifty-six".