1221051115 has 8 divisors (see below), whose sum is σ = 1479769488. Its totient is φ = 967168800.

The previous prime is 1221051103. The next prime is 1221051121. The reversal of 1221051115 is 5111501221.

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

It is a de Polignac number, because none of the positive numbers 2^k-1221051115 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221051092 and 1221051101.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1208457 + ... + 1209466.

It is an arithmetic number, because the mean of its divisors is an integer number (184971186).

Almost surely, 2^1221051115 is an apocalyptic number.

1221051115 is a deficient number, since it is larger than the sum of its proper divisors (258718373).

1221051115 is a wasteful number, since it uses less digits than its factorization.

1221051115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2418029.

The product of its (nonzero) digits is 100, while the sum is 19.

The square root of 1221051115 is about 34943.5418210576. The cubic root of 1221051115 is about 1068.8365129972.

Adding to 1221051115 its reverse (5111501221), we get a palindrome (6332552336).

The spelling of 1221051115 in words is "one billion, two hundred twenty-one million, fifty-one thousand, one hundred fifteen".