1640782636 has 24 divisors (see below), whose sum is σ = 2938093200. Its totient is φ = 801508800.

The previous prime is 1640782609. The next prime is 1640782651. The reversal of 1640782636 is 6362870461.

It is a junction number, because it is equal to n+sod(n) for n = 1640782592 and 1640782601.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13791 + ... + 58921.

It is an arithmetic number, because the mean of its divisors is an integer number (122420550).

Almost surely, 2^1640782636 is an apocalyptic number.

It is an amenable number.

1640782636 is a deficient number, since it is larger than the sum of its proper divisors (1297310564).

1640782636 is a wasteful number, since it uses less digits than its factorization.

1640782636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45345 (or 45343 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

The square root of 1640782636 is about 40506.5752193394. The cubic root of 1640782636 is about 1179.4612680108.

The spelling of 1640782636 in words is "one billion, six hundred forty million, seven hundred eighty-two thousand, six hundred thirty-six".