1011212021 has 4 divisors (see below), whose sum is σ = 1012785312. Its totient is φ = 1009638732.

The previous prime is 1011212011. The next prime is 1011212029. The reversal of 1011212021 is 1202121101.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1202121101 = 9817 ⋅122453.

It is a cyclic number.

It is not a de Polignac number, because 1011212021 - 2¹⁰ = 1011210997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1011211993 and 1011212011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011212029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 785681 + ... + 786966.

It is an arithmetic number, because the mean of its divisors is an integer number (253196328).

Almost surely, 2^1011212021 is an apocalyptic number.

It is an amenable number.

1011212021 is a deficient number, since it is larger than the sum of its proper divisors (1573291).

1011212021 is an equidigital number, since it uses as much as digits as its factorization.

1011212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1573290.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1011212021 is about 31799.5600755734. The cubic root of 1011212021 is about 1003.7234589790.

Adding to 1011212021 its reverse (1202121101), we get a palindrome (2213333122).

The spelling of 1011212021 in words is "one billion, eleven million, two hundred twelve thousand, twenty-one".