1216280154778 has 16 divisors (see below), whose sum is σ = 1964779318656. Its totient is φ = 561354623280.

The previous prime is 1216280154773. The next prime is 1216280154779. The reversal of 1216280154778 is 8774510826121.

It is not an unprimeable number, because it can be changed into a prime (1216280154773) 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, 3961875 + ... + 4257817.

It is an arithmetic number, because the mean of its divisors is an integer number (122798707416).

Almost surely, 2^{1216280154778} is an apocalyptic number.

1216280154778 is a deficient number, since it is larger than the sum of its proper divisors (748499163878).

1216280154778 is a wasteful number, since it uses less digits than its factorization.

1216280154778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454029.

The product of its (nonzero) digits is 1505280, while the sum is 52.

The spelling of 1216280154778 in words is "one trillion, two hundred sixteen billion, two hundred eighty million, one hundred fifty-four thousand, seven hundred seventy-eight".