1221531343441 has 32 divisors (see below), whose sum is σ = 1344232713600. Its totient is φ = 1105900024320.

The previous prime is 1221531343411. The next prime is 1221531343463. The reversal of 1221531343441 is 1443431351221.

It is a cyclic number.

It is not a de Polignac number, because 1221531343441 - 2³⁵ = 1187171605073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221531343397 and 1221531343406.

It is not an unprimeable number, because it can be changed into a prime (1221531343411) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25532755 + ... + 25580551.

It is an arithmetic number, because the mean of its divisors is an integer number (42007272300).

Almost surely, 2^{1221531343441} is an apocalyptic number.

It is an amenable number.

1221531343441 is a deficient number, since it is larger than the sum of its proper divisors (122701370159).

1221531343441 is a wasteful number, since it uses less digits than its factorization.

1221531343441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48529.

The product of its digits is 34560, while the sum is 34.

Adding to 1221531343441 its reverse (1443431351221), we get a palindrome (2664962694662).

The spelling of 1221531343441 in words is "one trillion, two hundred twenty-one billion, five hundred thirty-one million, three hundred forty-three thousand, four hundred forty-one".