1221116013 has 32 divisors (see below), whose sum is σ = 1960716800. Its totient is φ = 746635968.

The previous prime is 1221115999. The next prime is 1221116033. The reversal of 1221116013 is 3106111221.

It is not a de Polignac number, because 1221116013 - 2⁵ = 1221115981 is a prime.

It is a super-3 number, since 3×1221116013³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221116033) 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, 44028 + ... + 66186.

It is an arithmetic number, because the mean of its divisors is an integer number (61272400).

Almost surely, 2^1221116013 is an apocalyptic number.

1221116013 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1221116013 is a deficient number, since it is larger than the sum of its proper divisors (739600787).

1221116013 is a wasteful number, since it uses less digits than its factorization.

1221116013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22338 (or 22332 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 1221116013 is about 34944.4704209407. The cubic root of 1221116013 is about 1068.8554486291.

Adding to 1221116013 its reverse (3106111221), we get a palindrome (4327227234).

It can be divided in two parts, 12211 and 16013, that added together give a square (28224 = 168²).

The spelling of 1221116013 in words is "one billion, two hundred twenty-one million, one hundred sixteen thousand, thirteen".