663661402 has 8 divisors (see below), whose sum is σ = 1054050516. Its totient is φ = 312311232.

The previous prime is 663661399. The next prime is 663661409. The reversal of 663661402 is 204166366.

It can be written as a sum of positive squares in 2 ways, for example, as 491553241 + 172108161 = 22171^2 + 13119^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (34), and also a Moran number because the ratio is a prime number: 19519453 = 663661402 / (6 + 6 + 3 + 6 + 6 + 1 + 4 + 0 + 2).

It is not an unprimeable number, because it can be changed into a prime (663661409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9759693 + ... + 9759760.

Almost surely, 2^663661402 is an apocalyptic number.

663661402 is a deficient number, since it is larger than the sum of its proper divisors (390389114).

663661402 is a wasteful number, since it uses less digits than its factorization.

663661402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19519472.

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 663661402 is about 25761.6265402633. The cubic root of 663661402 is about 872.2658170688.

The spelling of 663661402 in words is "six hundred sixty-three million, six hundred sixty-one thousand, four hundred two".