1221618036 has 12 divisors (see below), whose sum is σ = 2850442112. Its totient is φ = 407206008.

The previous prime is 1221618019. The next prime is 1221618061. The reversal of 1221618036 is 6308161221.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 1221617994 and 1221618012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50900740 + ... + 50900763.

Almost surely, 2^1221618036 is an apocalyptic number.

It is an amenable number.

1221618036 is an abundant number, since it is smaller than the sum of its proper divisors (1628824076).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221618036 is a wasteful number, since it uses less digits than its factorization.

1221618036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101801510 (or 101801508 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 1221618036 is about 34951.6528364540. The cubic root of 1221618036 is about 1069.0019038651.

Adding to 1221618036 its reverse (6308161221), we get a palindrome (7529779257).

The spelling of 1221618036 in words is "one billion, two hundred twenty-one million, six hundred eighteen thousand, thirty-six".