1216456545 has 16 divisors (see below), whose sum is σ = 2030954112. Its totient is φ = 620568960.

The previous prime is 1216456543. The next prime is 1216456547. The reversal of 1216456545 is 5456546121.

It is an interprime number because it is at equal distance from previous prime (1216456543) and next prime (1216456547).

It is not a de Polignac number, because 1216456545 - 2¹ = 1216456543 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1216456543) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1762636 + ... + 1763325.

It is an arithmetic number, because the mean of its divisors is an integer number (126934632).

Almost surely, 2^1216456545 is an apocalyptic number.

1216456545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1216456545 is a deficient number, since it is larger than the sum of its proper divisors (814497567).

1216456545 is a wasteful number, since it uses less digits than its factorization.

1216456545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3525992.

The product of its digits is 144000, while the sum is 39.

The square root of 1216456545 is about 34877.7370968932. The cubic root of 1216456545 is about 1067.4942223177.

The spelling of 1216456545 in words is "one billion, two hundred sixteen million, four hundred fifty-six thousand, five hundred forty-five".