1212103021 has 4 divisors (see below), whose sum is σ = 1232647200. Its totient is φ = 1191558844.

The previous prime is 1212103003. The next prime is 1212103037. The reversal of 1212103021 is 1203012121.

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: 1203012121 = 821 ⋅1465301.

It is a cyclic number.

It is not a de Polignac number, because 1212103021 - 2⁵ = 1212102989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212102992 and 1212103010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212103051) 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, 10272001 + ... + 10272118.

It is an arithmetic number, because the mean of its divisors is an integer number (308161800).

Almost surely, 2^1212103021 is an apocalyptic number.

It is an amenable number.

1212103021 is a deficient number, since it is larger than the sum of its proper divisors (20544179).

1212103021 is an equidigital number, since it uses as much as digits as its factorization.

1212103021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20544178.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1212103021 is about 34815.2699400708. The cubic root of 1212103021 is about 1066.2192303842.

Adding to 1212103021 its reverse (1203012121), we get a palindrome (2415115142).

The spelling of 1212103021 in words is "one billion, two hundred twelve million, one hundred three thousand, twenty-one".