663664645 has 8 divisors (see below), whose sum is σ = 910168704. Its totient is φ = 455084304.

The previous prime is 663664643. The next prime is 663664657. The reversal of 663664645 is 546466366.

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 663664645 - 2¹ = 663664643 is a prime.

It is a super-2 number, since 2×663664645² = 880901522045952050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 663664595 and 663664604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663664643) 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, 9480889 + ... + 9480958.

It is an arithmetic number, because the mean of its divisors is an integer number (113771088).

Almost surely, 2^663664645 is an apocalyptic number.

It is an amenable number.

663664645 is a deficient number, since it is larger than the sum of its proper divisors (246504059).

663664645 is a wasteful number, since it uses less digits than its factorization.

663664645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18961859.

The product of its digits is 1866240, while the sum is 46.

The square root of 663664645 is about 25761.6894826407. The cubic root of 663664645 is about 872.2672378502.

The spelling of 663664645 in words is "six hundred sixty-three million, six hundred sixty-four thousand, six hundred forty-five".