1212021 has 6 divisors (see below), whose sum is σ = 1750710. Its totient is φ = 808008.

The previous prime is 1212017. The next prime is 1212023. The reversal of 1212021 is 1202121.

It can be written as a sum of positive squares in only one way, i.e., 1199025 + 12996 = 1095^2 + 114^2 .

It is not a de Polignac number, because 1212021 - 2² = 1212017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 134669 = 1212021 / (1 + 2 + 1 + 2 + 0 + 2 + 1).

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 1211994 and 1212012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212023) 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 5 ways as a sum of consecutive naturals, for example, 67326 + ... + 67343.

It is an arithmetic number, because the mean of its divisors is an integer number (291785).

2^1212021 is an apocalyptic number.

It is an amenable number.

1212021 is a deficient number, since it is larger than the sum of its proper divisors (538689).

1212021 is a wasteful number, since it uses less digits than its factorization.

1212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134675 (or 134672 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1212021 is about 1100.9182530960. The cubic root of 1212021 is about 106.6195180080.

Adding to 1212021 its reverse (1202121), we get a palindrome (2414142).

The spelling of 1212021 in words is "one million, two hundred twelve thousand, twenty-one".