1261892668 has 6 divisors (see below), whose sum is σ = 2208312176. Its totient is φ = 630946332.

The previous prime is 1261892647. The next prime is 1261892669. The reversal of 1261892668 is 8662981621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261892669) 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 as a sum of consecutive naturals, namely, 157736580 + ... + 157736587.

Almost surely, 2^1261892668 is an apocalyptic number.

It is an amenable number.

1261892668 is a deficient number, since it is larger than the sum of its proper divisors (946419508).

1261892668 is a wasteful number, since it uses less digits than its factorization.

1261892668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315473171 (or 315473169 counting only the distinct ones).

The product of its digits is 497664, while the sum is 49.

The square root of 1261892668 is about 35523.1286347360. The cubic root of 1261892668 is about 1080.6228311905.

The spelling of 1261892668 in words is "one billion, two hundred sixty-one million, eight hundred ninety-two thousand, six hundred sixty-eight".