1663960839 has 4 divisors (see below), whose sum is σ = 2218614456. Its totient is φ = 1109307224.

The previous prime is 1663960819. The next prime is 1663960841. The reversal of 1663960839 is 9380693661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1663960839 - 2¹⁷ = 1663829767 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1663960791 and 1663960800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663960819) 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, 277326804 + ... + 277326809.

It is an arithmetic number, because the mean of its divisors is an integer number (554653614).

Almost surely, 2^1663960839 is an apocalyptic number.

1663960839 is a deficient number, since it is larger than the sum of its proper divisors (554653617).

1663960839 is an equidigital number, since it uses as much as digits as its factorization.

1663960839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554653616.

The product of its (nonzero) digits is 1259712, while the sum is 51.

The square root of 1663960839 is about 40791.6760994201. The cubic root of 1663960839 is about 1184.9891312717.

The spelling of 1663960839 in words is "one billion, six hundred sixty-three million, nine hundred sixty thousand, eight hundred thirty-nine".