1221235513 has 8 divisors (see below), whose sum is σ = 1250877600. Its totient is φ = 1191891648.

The previous prime is 1221235493. The next prime is 1221235517. The reversal of 1221235513 is 3155321221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221235513 - 2²⁹ = 684364601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221235517) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66256 + ... + 82657.

It is an arithmetic number, because the mean of its divisors is an integer number (156359700).

Almost surely, 2^1221235513 is an apocalyptic number.

It is an amenable number.

1221235513 is a deficient number, since it is larger than the sum of its proper divisors (29642087).

1221235513 is a wasteful number, since it uses less digits than its factorization.

1221235513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149111.

The product of its digits is 1800, while the sum is 25.

The square root of 1221235513 is about 34946.1802347553. The cubic root of 1221235513 is about 1068.8903140195.

Adding to 1221235513 its reverse (3155321221), we get a palindrome (4376556734).

The spelling of 1221235513 in words is "one billion, two hundred twenty-one million, two hundred thirty-five thousand, five hundred thirteen".