631666733620 has 72 divisors (see below), whose sum is σ = 1437739624440. Its totient is φ = 233011284480.

The previous prime is 631666733609. The next prime is 631666733623. The reversal of 631666733620 is 26337666136.

It can be written as a sum of positive squares in 12 ways, for example, as 561507438244 + 70159295376 = 749338^2 + 264876^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631666733623) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3525810 + ... + 3700630.

It is an arithmetic number, because the mean of its divisors is an integer number (19968605895).

Almost surely, 2^631666733620 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 631666733620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (718869812220).

631666733620 is an abundant number, since it is smaller than the sum of its proper divisors (806072890820).

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

631666733620 is a wasteful number, since it uses less digits than its factorization.

631666733620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175925 (or 175910 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 49.

The spelling of 631666733620 in words is "six hundred thirty-one billion, six hundred sixty-six million, seven hundred thirty-three thousand, six hundred twenty".