1216601128 has 32 divisors (see below), whose sum is σ = 2308188960. Its totient is φ = 601113280.

The previous prime is 1216601101. The next prime is 1216601129. The reversal of 1216601128 is 8211066121.

1216601128 is a nontrivial binomial coefficient, being equal to C(49328, 2).

It is a junction number, because it is equal to n+sod(n) for n = 1216601096 and 1216601105.

It is not an unprimeable number, because it can be changed into a prime (1216601129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 393075 + ... + 396157.

It is an arithmetic number, because the mean of its divisors is an integer number (72130905).

Almost surely, 2^1216601128 is an apocalyptic number.

1216601128 is the 49327-th triangular number and also the 24664-th hexagonal number.

1216601128 is the 16443-rd centered nonagonal number.

It is an amenable number.

1216601128 is a deficient number, since it is larger than the sum of its proper divisors (1091587832).

1216601128 is a wasteful number, since it uses less digits than its factorization.

1216601128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3657 (or 3653 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 1216601128 is about 34879.8097471876. The cubic root of 1216601128 is about 1067.5365132935.

Adding to 1216601128 its reverse (8211066121), we get a palindrome (9427667249).

The spelling of 1216601128 in words is "one billion, two hundred sixteen million, six hundred one thousand, one hundred twenty-eight".