1216472981 has 2 divisors, whose sum is σ = 1216472982. Its totient is φ = 1216472980.

The previous prime is 1216472963. The next prime is 1216473019. The reversal of 1216472981 is 1892746121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 637108081 + 579364900 = 25241^2 + 24070^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1216472981 is a prime.

It is a super-2 number, since 2×1216472981² = 2959613027006052722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216402981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608236490 + 608236491.

It is an arithmetic number, because the mean of its divisors is an integer number (608236491).

Almost surely, 2^1216472981 is an apocalyptic number.

It is an amenable number.

1216472981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216472981 is an equidigital number, since it uses as much as digits as its factorization.

1216472981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 41.

The square root of 1216472981 is about 34877.9727191819. The cubic root of 1216472981 is about 1067.4990300675.

The spelling of 1216472981 in words is "one billion, two hundred sixteen million, four hundred seventy-two thousand, nine hundred eighty-one".