1216166228451 has 48 divisors (see below), whose sum is σ = 1792766342016. Its totient is φ = 794266881408.

The previous prime is 1216166228357. The next prime is 1216166228479. The reversal of 1216166228451 is 1548226616121.

1216166228451 is a `hidden beast` number, since 1 + 2 + 1 + 6 + 16 + 622 + 8 + 4 + 5 + 1 = 666.

It is not a de Polignac number, because 1216166228451 - 2³⁴ = 1198986359267 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1216166228397 and 1216166228406.

It is not an unprimeable number, because it can be changed into a prime (1216166229451) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 124055716 + ... + 124065518.

It is an arithmetic number, because the mean of its divisors is an integer number (37349298792).

Almost surely, 2^{1216166228451} is an apocalyptic number.

1216166228451 is a deficient number, since it is larger than the sum of its proper divisors (576600113565).

1216166228451 is a wasteful number, since it uses less digits than its factorization.

1216166228451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10992 (or 10989 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The spelling of 1216166228451 in words is "one trillion, two hundred sixteen billion, one hundred sixty-six million, two hundred twenty-eight thousand, four hundred fifty-one".