1205163663 has 16 divisors (see below), whose sum is σ = 1753978752. Its totient is φ = 729980000.

The previous prime is 1205163653. The next prime is 1205163671. The reversal of 1205163663 is 3663615021.

It is a cyclic number.

It is not a de Polignac number, because 1205163663 - 2⁴ = 1205163647 is a prime.

It is a super-5 number, since 5×1205163663⁵ (a number of 47 digits) contains 55555 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1205163653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53128 + ... + 72338.

It is an arithmetic number, because the mean of its divisors is an integer number (109623672).

Almost surely, 2^1205163663 is an apocalyptic number.

1205163663 is a deficient number, since it is larger than the sum of its proper divisors (548815089).

1205163663 is a wasteful number, since it uses less digits than its factorization.

1205163663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21126.

The product of its (nonzero) digits is 19440, while the sum is 33.

The square root of 1205163663 is about 34715.4672012347. The cubic root of 1205163663 is about 1064.1806133247.

Adding to 1205163663 its reverse (3663615021), we get a palindrome (4868778684).

The spelling of 1205163663 in words is "one billion, two hundred five million, one hundred sixty-three thousand, six hundred sixty-three".