212102421 has 16 divisors (see below), whose sum is σ = 299781504. Its totient is φ = 132931584.

The previous prime is 212102417. The next prime is 212102467. The reversal of 212102421 is 124201212.

It is not a de Polignac number, because 212102421 - 2² = 212102417 is a prime.

It is a super-2 number, since 2×212102421² = 89974873988122482, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 212102421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212102221) 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 15 ways as a sum of consecutive naturals, for example, 57000 + ... + 60606.

It is an arithmetic number, because the mean of its divisors is an integer number (18736344).

Almost surely, 2^212102421 is an apocalyptic number.

It is an amenable number.

212102421 is a deficient number, since it is larger than the sum of its proper divisors (87679083).

212102421 is a wasteful number, since it uses less digits than its factorization.

212102421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4780.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 212102421 is about 14563.7365054439. The cubic root of 212102421 is about 596.3692037379.

Adding to 212102421 its reverse (124201212), we get a palindrome (336303633).

The spelling of 212102421 in words is "two hundred twelve million, one hundred two thousand, four hundred twenty-one".