1299669921 has 16 divisors (see below), whose sum is σ = 2100477120. Its totient is φ = 787678560.

The previous prime is 1299669871. The next prime is 1299669929.

1299669921 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1299669921 - 2¹⁹ = 1299145633 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1299669929) 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 15 ways as a sum of consecutive naturals, for example, 2187700 + ... + 2188293.

It is an arithmetic number, because the mean of its divisors is an integer number (131279820).

Almost surely, 2^1299669921 is an apocalyptic number.

1299669921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1299669921 is a deficient number, since it is larger than the sum of its proper divisors (800807199).

1299669921 is a wasteful number, since it uses less digits than its factorization.

1299669921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4376013 (or 4376007 counting only the distinct ones).

The product of its digits is 944784, while the sum is 54.

The square root of 1299669921 is about 36050.9350918946. The cubic root of 1299669921 is about 1091.3005045059.

The spelling of 1299669921 in words is "one billion, two hundred ninety-nine million, six hundred sixty-nine thousand, nine hundred twenty-one".