211221010004 has 12 divisors (see below), whose sum is σ = 370817717844. Its totient is φ = 105273090624.

The previous prime is 211221010003. The next prime is 211221010109. The reversal of 211221010004 is 400010122112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 78877845904 + 132343164100 = 280852^2 + 363790^2 .

It is a super-2 number, since 2×211221010004² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221010003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84352187 + ... + 84354690.

It is an arithmetic number, because the mean of its divisors is an integer number (30901476487).

Almost surely, 2^211221010004 is an apocalyptic number.

It is an amenable number.

211221010004 is a deficient number, since it is larger than the sum of its proper divisors (159596707840).

211221010004 is a wasteful number, since it uses less digits than its factorization.

211221010004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168707194 (or 168707192 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 211221010004 its reverse (400010122112), we get a palindrome (611231132116).

The spelling of 211221010004 in words is "two hundred eleven billion, two hundred twenty-one million, ten thousand, four".