211242421 has 8 divisors (see below), whose sum is σ = 228130560. Its totient is φ = 194445552.

The previous prime is 211242407. The next prime is 211242469. The reversal of 211242421 is 124242112.

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

It is a cyclic number.

It is not a de Polignac number, because 211242421 - 2⁹ = 211241909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211242481) 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, 17965 + ... + 27298.

It is an arithmetic number, because the mean of its divisors is an integer number (28516320).

Almost surely, 2^211242421 is an apocalyptic number.

It is an amenable number.

211242421 is a deficient number, since it is larger than the sum of its proper divisors (16888139).

211242421 is a wasteful number, since it uses less digits than its factorization.

211242421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45635.

The product of its digits is 256, while the sum is 19.

The square root of 211242421 is about 14534.1811258839. The cubic root of 211242421 is about 595.5620901161.

Adding to 211242421 its reverse (124242112), we get a palindrome (335484533).

The spelling of 211242421 in words is "two hundred eleven million, two hundred forty-two thousand, four hundred twenty-one".