1216245662531 has 12 divisors (see below), whose sum is σ = 1272959194080. Its totient is φ = 1161961661520.

The previous prime is 1216245662497. The next prime is 1216245662537. The reversal of 1216245662531 is 1352665426121.

It is not a de Polignac number, because 1216245662531 - 2³⁰ = 1215171920707 is a prime.

It is a super-2 number, since 2×1216245662531² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216245662537) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 948155 + ... + 1825236.

It is an arithmetic number, because the mean of its divisors is an integer number (106079932840).

Almost surely, 2^{1216245662531} is an apocalyptic number.

1216245662531 is a deficient number, since it is larger than the sum of its proper divisors (56713531549).

1216245662531 is an equidigital number, since it uses as much as digits as its factorization.

1216245662531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2774266 (or 2774243 counting only the distinct ones).

The product of its digits is 518400, while the sum is 44.

The spelling of 1216245662531 in words is "one trillion, two hundred sixteen billion, two hundred forty-five million, six hundred sixty-two thousand, five hundred thirty-one".