1640566363 has 4 divisors (see below), whose sum is σ = 1645841808. Its totient is φ = 1635290920.

The previous prime is 1640566357. The next prime is 1640566393. The reversal of 1640566363 is 3636650461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3636650461 = 127 ⋅28635043.

It is a cyclic number.

It is not a de Polignac number, because 1640566363 - 2²⁹ = 1103695451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1640566393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2637256 + ... + 2637877.

It is an arithmetic number, because the mean of its divisors is an integer number (411460452).

Almost surely, 2^1640566363 is an apocalyptic number.

1640566363 is a deficient number, since it is larger than the sum of its proper divisors (5275445).

1640566363 is an equidigital number, since it uses as much as digits as its factorization.

1640566363 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5275444.

The product of its (nonzero) digits is 233280, while the sum is 40.

The square root of 1640566363 is about 40503.9055277389. The cubic root of 1640566363 is about 1179.4094437919.

The spelling of 1640566363 in words is "one billion, six hundred forty million, five hundred sixty-six thousand, three hundred sixty-three".