1640662511 has 4 divisors (see below), whose sum is σ = 1675570272. Its totient is φ = 1605754752.

The previous prime is 1640662493. The next prime is 1640662523. The reversal of 1640662511 is 1152660461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1152660461 = 7331 ⋅157231.

It is a cyclic number.

It is not a de Polignac number, because 1640662511 - 2³⁰ = 566920687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640662811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17453810 + ... + 17453903.

It is an arithmetic number, because the mean of its divisors is an integer number (418892568).

Almost surely, 2^1640662511 is an apocalyptic number.

1640662511 is a deficient number, since it is larger than the sum of its proper divisors (34907761).

1640662511 is an equidigital number, since it uses as much as digits as its factorization.

1640662511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34907760.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 1640662511 is about 40505.0924082392. The cubic root of 1640662511 is about 1179.4324837303.

The spelling of 1640662511 in words is "one billion, six hundred forty million, six hundred sixty-two thousand, five hundred eleven".