1631600640 has 180 divisors, whose sum is σ = 5658598764. Its totient is φ = 434896896.

The previous prime is 1631600609. The next prime is 1631600647. The reversal of 1631600640 is 460061361.

1631600640 is a `hidden beast` number, since 1 + 6 + 3 + 16 + 0 + 0 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1248067584 + 383533056 = 35328^2 + 19584^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1631600647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 736174 + ... + 738386.

Almost surely, 2^1631600640 is an apocalyptic number.

1631600640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1631600640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2829299382).

1631600640 is an abundant number, since it is smaller than the sum of its proper divisors (4026998124).

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

1631600640 is an equidigital number, since it uses as much as digits as its factorization.

1631600640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2252 (or 2223 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 1631600640 is about 40393.0766344927. The cubic root of 1631600640 is about 1177.2570204687.

The spelling of 1631600640 in words is "one billion, six hundred thirty-one million, six hundred thousand, six hundred forty".