663964769 has 8 divisors (see below), whose sum is σ = 715862952. Its totient is φ = 612184320.

The previous prime is 663964757. The next prime is 663964771. The reversal of 663964769 is 967469366.

It can be written as a sum of positive squares in 4 ways, for example, as 24127744 + 639837025 = 4912^2 + 25295^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 663964769 - 2⁴ = 663964753 is a prime.

It is a super-2 number, since 2×663964769² = 881698428946446722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (663964729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17534 + ... + 40439.

It is an arithmetic number, because the mean of its divisors is an integer number (89482869).

Almost surely, 2^663964769 is an apocalyptic number.

It is an amenable number.

663964769 is a deficient number, since it is larger than the sum of its proper divisors (51898183).

663964769 is a wasteful number, since it uses less digits than its factorization.

663964769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58867.

The product of its digits is 8817984, while the sum is 56.

The square root of 663964769 is about 25767.5138304028. The cubic root of 663964769 is about 872.3987042880.

The spelling of 663964769 in words is "six hundred sixty-three million, nine hundred sixty-four thousand, seven hundred sixty-nine".