1286693661 has 64 divisors (see below), whose sum is σ = 2024985600. Its totient is φ = 718502400.

The previous prime is 1286693627. The next prime is 1286693677. The reversal of 1286693661 is 1663966821.

It is not a de Polignac number, because 1286693661 - 2¹⁰ = 1286692637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1286693661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286693621) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4578841 + ... + 4579121.

It is an arithmetic number, because the mean of its divisors is an integer number (31640400).

Almost surely, 2^1286693661 is an apocalyptic number.

1286693661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1286693661 is a deficient number, since it is larger than the sum of its proper divisors (738291939).

1286693661 is a wasteful number, since it uses less digits than its factorization.

1286693661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490.

The product of its digits is 559872, while the sum is 48.

The square root of 1286693661 is about 35870.5124161894. The cubic root of 1286693661 is about 1087.6564019737.

The spelling of 1286693661 in words is "one billion, two hundred eighty-six million, six hundred ninety-three thousand, six hundred sixty-one".