213001421 has 4 divisors (see below), whose sum is σ = 213030972. Its totient is φ = 212971872.

The previous prime is 213001379. The next prime is 213001423. The reversal of 213001421 is 124100312.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 121110025 + 91891396 = 11005^2 + 9586^2 .

It is a cyclic number.

It is not a de Polignac number, because 213001421 - 2¹⁸ = 212739277 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213001396 and 213001405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213001423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3935 + ... + 21011.

It is an arithmetic number, because the mean of its divisors is an integer number (53257743).

Almost surely, 2^213001421 is an apocalyptic number.

It is an amenable number.

213001421 is a deficient number, since it is larger than the sum of its proper divisors (29551).

213001421 is a wasteful number, since it uses less digits than its factorization.

213001421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29550.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 213001421 is about 14594.5682019031. The cubic root of 213001421 is about 597.2105900460.

Adding to 213001421 its reverse (124100312), we get a palindrome (337101733).

The spelling of 213001421 in words is "two hundred thirteen million, one thousand, four hundred twenty-one".