663655641 has 16 divisors (see below), whose sum is σ = 971247360. Its totient is φ = 399744720.

The previous prime is 663655637. The next prime is 663655649. The reversal of 663655641 is 146556366.

It is not a de Polignac number, because 663655641 - 2² = 663655637 is a prime.

It is a super-2 number, since 2×663655641² = 880877619662241762, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 663655593 and 663655602.

It is not an unprimeable number, because it can be changed into a prime (663655649) 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, 56311 + ... + 67068.

It is an arithmetic number, because the mean of its divisors is an integer number (60702960).

Almost surely, 2^663655641 is an apocalyptic number.

It is an amenable number.

663655641 is a deficient number, since it is larger than the sum of its proper divisors (307591719).

663655641 is a wasteful number, since it uses less digits than its factorization.

663655641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123556.

The product of its digits is 388800, while the sum is 42.

The square root of 663655641 is about 25761.5147264286. The cubic root of 663655641 is about 872.2632931221.

The spelling of 663655641 in words is "six hundred sixty-three million, six hundred fifty-five thousand, six hundred forty-one".