1221309481 has 8 divisors (see below), whose sum is σ = 1396047744. Its totient is φ = 1046637600.

The previous prime is 1221309469. The next prime is 1221309497. The reversal of 1221309481 is 1849031221.

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 1221309481 - 2²¹ = 1219212329 is a prime.

It is a super-2 number, since 2×1221309481² = 2983193696760978722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221309421) 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, 32541 + ... + 59173.

It is an arithmetic number, because the mean of its divisors is an integer number (174505968).

Almost surely, 2^1221309481 is an apocalyptic number.

It is an amenable number.

1221309481 is a deficient number, since it is larger than the sum of its proper divisors (174738263).

1221309481 is an equidigital number, since it uses as much as digits as its factorization.

1221309481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33191.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 1221309481 is about 34947.2385318211. The cubic root of 1221309481 is about 1068.9118938272.

The spelling of 1221309481 in words is "one billion, two hundred twenty-one million, three hundred nine thousand, four hundred eighty-one".