1551221116 has 12 divisors (see below), whose sum is σ = 2717003520. Its totient is φ = 774934400.

The previous prime is 1551221099. The next prime is 1551221129. The reversal of 1551221116 is 6111221551.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 163861 + ... + 173068.

It is an arithmetic number, because the mean of its divisors is an integer number (226416960).

Almost surely, 2^1551221116 is an apocalyptic number.

It is an amenable number.

1551221116 is a deficient number, since it is larger than the sum of its proper divisors (1165782404).

1551221116 is a wasteful number, since it uses less digits than its factorization.

1551221116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338084 (or 338082 counting only the distinct ones).

The product of its digits is 600, while the sum is 25.

The square root of 1551221116 is about 39385.5445055670. The cubic root of 1551221116 is about 1157.5983595026.

Adding to 1551221116 its reverse (6111221551), we get a palindrome (7662442667).

The spelling of 1551221116 in words is "one billion, five hundred fifty-one million, two hundred twenty-one thousand, one hundred sixteen".