1211404011021 has 16 divisors (see below), whose sum is σ = 1794773937600. Its totient is φ = 807557076144.

The previous prime is 1211404011011. The next prime is 1211404011031. The reversal of 1211404011021 is 1201104041121.

1211404011021 is a `hidden beast` number, since 1 + 21 + 140 + 401 + 102 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (1211404011011) and next prime (1211404011031).

It is not a de Polignac number, because 1211404011021 - 2¹⁷ = 1211403879949 is a prime.

It is a super-3 number, since 3×1211404011021³ (a number of 37 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1211404010985 and 1211404011003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211404011011) 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 15 ways as a sum of consecutive naturals, for example, 776091 + ... + 1739288.

It is an arithmetic number, because the mean of its divisors is an integer number (112173371100).

Almost surely, 2^{1211404011021} is an apocalyptic number.

It is an amenable number.

1211404011021 is a deficient number, since it is larger than the sum of its proper divisors (583369926579).

1211404011021 is a wasteful number, since it uses less digits than its factorization.

1211404011021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2533225 (or 2533219 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1211404011021 its reverse (1201104041121), we get a palindrome (2412508052142).

The spelling of 1211404011021 in words is "one trillion, two hundred eleven billion, four hundred four million, eleven thousand, twenty-one".