1205868685021 has 32 divisors (see below), whose sum is σ = 1632449339136. Its totient is φ = 867358008000.

The previous prime is 1205868685001. The next prime is 1205868685057.

1205868685021 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1205868685021 - 2¹¹ = 1205868682973 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1205868685021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1205868685001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4856830 + ... + 5099071.

It is an arithmetic number, because the mean of its divisors is an integer number (51014041848).

Almost surely, 2^{1205868685021} is an apocalyptic number.

1205868685021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1205868685021 is a deficient number, since it is larger than the sum of its proper divisors (426580654115).

1205868685021 is an equidigital number, since it uses as much as digits as its factorization.

1205868685021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9955954 (or 9955932 counting only the distinct ones).

The product of its (nonzero) digits is 1843200, while the sum is 52.

The spelling of 1205868685021 in words is "one trillion, two hundred five billion, eight hundred sixty-eight million, six hundred eighty-five thousand, twenty-one".