1216006556 has 6 divisors (see below), whose sum is σ = 2128011480. Its totient is φ = 608003276.

The previous prime is 1216006553. The next prime is 1216006559. The reversal of 1216006556 is 6556006121.

It is an interprime number because it is at equal distance from previous prime (1216006553) and next prime (1216006559).

It is a super-2 number, since 2×1216006556² = 2957343888469962272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216006553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152000816 + ... + 152000823.

It is an arithmetic number, because the mean of its divisors is an integer number (354668580).

Almost surely, 2^1216006556 is an apocalyptic number.

It is an amenable number.

1216006556 is a deficient number, since it is larger than the sum of its proper divisors (912004924).

1216006556 is a wasteful number, since it uses less digits than its factorization.

1216006556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304001643 (or 304001641 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 1216006556 is about 34871.2855512956. The cubic root of 1216006556 is about 1067.3625776916.

The spelling of 1216006556 in words is "one billion, two hundred sixteen million, six thousand, five hundred fifty-six".