1231302121 has 4 divisors (see below), whose sum is σ = 1407202432. Its totient is φ = 1055401812.

The previous prime is 1231302073. The next prime is 1231302131. The reversal of 1231302121 is 1212031321.

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: 1212031321 = 83 ⋅14602787.

It is a cyclic number.

It is not a de Polignac number, because 1231302121 - 2¹⁷ = 1231171049 is a prime.

It is a super-2 number, since 2×1231302121² = 3032209826358197282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231302095 and 1231302104.

It is not an unprimeable number, because it can be changed into a prime (1231302131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87950145 + ... + 87950158.

It is an arithmetic number, because the mean of its divisors is an integer number (351800608).

Almost surely, 2^1231302121 is an apocalyptic number.

It is an amenable number.

1231302121 is a deficient number, since it is larger than the sum of its proper divisors (175900311).

1231302121 is an equidigital number, since it uses as much as digits as its factorization.

1231302121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175900310.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1231302121 is about 35089.9148046843. The cubic root of 1231302121 is about 1071.8192247450.

Adding to 1231302121 its reverse (1212031321), we get a palindrome (2443333442).

The spelling of 1231302121 in words is "one billion, two hundred thirty-one million, three hundred two thousand, one hundred twenty-one".