2631684640 has 48 divisors (see below), whose sum is σ = 6695618328. Its totient is φ = 971698176.

The previous prime is 2631684617. The next prime is 2631684647. The reversal of 2631684640 is 464861362.

It can be written as a sum of positive squares in 4 ways, for example, as 1828075536 + 803609104 = 42756^2 + 28348^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 2631684593 and 2631684602.

It is not an unprimeable number, because it can be changed into a prime (2631684647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 630537 + ... + 634696.

Almost surely, 2^2631684640 is an apocalyptic number.

2631684640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2631684640 is an abundant number, since it is smaller than the sum of its proper divisors (4063933688).

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

2631684640 is a wasteful number, since it uses less digits than its factorization.

2631684640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265261 (or 1265253 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 40.

The square root of 2631684640 is about 51299.9477582580. The cubic root of 2631684640 is about 1380.6320426222.

The spelling of 2631684640 in words is "two billion, six hundred thirty-one million, six hundred eighty-four thousand, six hundred forty".