1654664663 has 4 divisors (see below), whose sum is σ = 1654773120. Its totient is φ = 1654556208.

The previous prime is 1654664659. The next prime is 1654664681. The reversal of 1654664663 is 3664664561.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3664664561 = 79 ⋅46388159.

It is a cyclic number.

It is not a de Polignac number, because 1654664663 - 2² = 1654664659 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 (1654664603) 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, 26678 + ... + 63411.

It is an arithmetic number, because the mean of its divisors is an integer number (413693280).

Almost surely, 2^1654664663 is an apocalyptic number.

1654664663 is a deficient number, since it is larger than the sum of its proper divisors (108457).

1654664663 is an equidigital number, since it uses as much as digits as its factorization.

1654664663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108456.

The product of its digits is 1866240, while the sum is 47.

The square root of 1654664663 is about 40677.5695316227. The cubic root of 1654664663 is about 1182.7782527527.

The spelling of 1654664663 in words is "one billion, six hundred fifty-four million, six hundred sixty-four thousand, six hundred sixty-three".