1221434131 has 16 divisors (see below), whose sum is σ = 1299214080. Its totient is φ = 1146562560.

The previous prime is 1221434129. The next prime is 1221434147. The reversal of 1221434131 is 1314341221.

It is a cyclic number.

It is not a de Polignac number, because 1221434131 - 2¹ = 1221434129 is a prime.

It is a super-2 number, since 2×1221434131² = 2983802672743450322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221434111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 142051 + ... + 150403.

It is an arithmetic number, because the mean of its divisors is an integer number (81200880).

Almost surely, 2^1221434131 is an apocalyptic number.

1221434131 is a deficient number, since it is larger than the sum of its proper divisors (77779949).

1221434131 is an equidigital number, since it uses as much as digits as its factorization.

1221434131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8526.

The product of its digits is 576, while the sum is 22.

The square root of 1221434131 is about 34949.0218890315. The cubic root of 1221434131 is about 1068.9482578930.

Adding to 1221434131 its reverse (1314341221), we get a palindrome (2535775352).

The spelling of 1221434131 in words is "one billion, two hundred twenty-one million, four hundred thirty-four thousand, one hundred thirty-one".