213100121 has 8 divisors (see below), whose sum is σ = 233823240. Its totient is φ = 192995712.

The previous prime is 213100079. The next prime is 213100157. The reversal of 213100121 is 121001312.

It can be written as a sum of positive squares in 4 ways, for example, as 42510400 + 170589721 = 6520^2 + 13061^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 213100121 - 2¹⁴ = 213083737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213108121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153956 + ... + 155333.

It is an arithmetic number, because the mean of its divisors is an integer number (29227905).

Almost surely, 2^213100121 is an apocalyptic number.

It is an amenable number.

213100121 is a deficient number, since it is larger than the sum of its proper divisors (20723119).

213100121 is a wasteful number, since it uses less digits than its factorization.

213100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309355.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 213100121 is about 14597.9492052822. The cubic root of 213100121 is about 597.3028203901.

Adding to 213100121 its reverse (121001312), we get a palindrome (334101433).

The spelling of 213100121 in words is "two hundred thirteen million, one hundred thousand, one hundred twenty-one".