16870121 has 4 divisors (see below), whose sum is σ = 16977732. Its totient is φ = 16762512.

The previous prime is 16870093. The next prime is 16870123. The reversal of 16870121 is 12107861.

16870121 is nontrivially palindromic in base 12.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2890000 + 13980121 = 1700^2 + 3739^2 .

It is a cyclic number.

It is not a de Polignac number, because 16870121 - 2⁶ = 16870057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16870123) 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 3 ways as a sum of consecutive naturals, for example, 53570 + ... + 53883.

It is an arithmetic number, because the mean of its divisors is an integer number (4244433).

Almost surely, 2^16870121 is an apocalyptic number.

It is an amenable number.

16870121 is a deficient number, since it is larger than the sum of its proper divisors (107611).

16870121 is a wasteful number, since it uses less digits than its factorization.

16870121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107610.

The product of its (nonzero) digits is 672, while the sum is 26.

The square root of 16870121 is about 4107.3252853895. The cubic root of 16870121 is about 256.4716696998.

Adding to 16870121 its reverse (12107861), we get a palindrome (28977982).

The spelling of 16870121 in words is "sixteen million, eight hundred seventy thousand, one hundred twenty-one".