211230421 has 4 divisors (see below), whose sum is σ = 211259500. Its totient is φ = 211201344.

The previous prime is 211230407. The next prime is 211230433. The reversal of 211230421 is 124032112.

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 190854225 + 20376196 = 13815^2 + 4514^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211230421 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211230395 and 211230404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211230221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6685 + ... + 21613.

It is an arithmetic number, because the mean of its divisors is an integer number (52814875).

Almost surely, 2^211230421 is an apocalyptic number.

It is an amenable number.

211230421 is a deficient number, since it is larger than the sum of its proper divisors (29079).

211230421 is a wasteful number, since it uses less digits than its factorization.

211230421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29078.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 211230421 is about 14533.7683000659. The cubic root of 211230421 is about 595.5508125826.

Adding to 211230421 its reverse (124032112), we get a palindrome (335262533).

The spelling of 211230421 in words is "two hundred eleven million, two hundred thirty thousand, four hundred twenty-one".