1263987 has 6 divisors (see below), whose sum is σ = 1825772. Its totient is φ = 842652.

The previous prime is 1263979. The next prime is 1264009. The reversal of 1263987 is 7893621.

1263987 is a `hidden beast` number, since 12 + 639 + 8 + 7 = 666.

It is not a de Polignac number, because 1263987 - 2³ = 1263979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1263917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 70213 + ... + 70230.

2^1263987 is an apocalyptic number.

1263987 is a deficient number, since it is larger than the sum of its proper divisors (561785).

1263987 is a wasteful number, since it uses less digits than its factorization.

1263987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140449 (or 140446 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 1263987 is about 1124.2717642990. The cubic root of 1263987 is about 108.1220328409.

The spelling of 1263987 in words is "one million, two hundred sixty-three thousand, nine hundred eighty-seven".