1285553663 has 4 divisors (see below), whose sum is σ = 1327023168. Its totient is φ = 1244084160.

The previous prime is 1285553629. The next prime is 1285553701. The reversal of 1285553663 is 3663555821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3663555821 = 919 ⋅3986459.

It is a cyclic number.

It is not a de Polignac number, because 1285553663 - 2⁸ = 1285553407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285553603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20734706 + ... + 20734767.

It is an arithmetic number, because the mean of its divisors is an integer number (331755792).

Almost surely, 2^1285553663 is an apocalyptic number.

1285553663 is a deficient number, since it is larger than the sum of its proper divisors (41469505).

1285553663 is an equidigital number, since it uses as much as digits as its factorization.

1285553663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41469504.

The product of its digits is 648000, while the sum is 44.

The square root of 1285553663 is about 35854.6184333344. The cubic root of 1285553663 is about 1087.3350894168.

The spelling of 1285553663 in words is "one billion, two hundred eighty-five million, five hundred fifty-three thousand, six hundred sixty-three".