9216955981 has 2 divisors, whose sum is σ = 9216955982. Its totient is φ = 9216955980.

The previous prime is 9216955973. The next prime is 9216955997. The reversal of 9216955981 is 1895596129.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8717209956 + 499746025 = 93366^2 + 22355^2 .

It is a cyclic number.

It is not a de Polignac number, because 9216955981 - 2³ = 9216955973 is a prime.

It is a super-2 number, since 2×9216955981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9216955901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4608477990 + 4608477991.

It is an arithmetic number, because the mean of its divisors is an integer number (4608477991).

Almost surely, 2^9216955981 is an apocalyptic number.

It is an amenable number.

9216955981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9216955981 is an equidigital number, since it uses as much as digits as its factorization.

9216955981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1749600, while the sum is 55.

The square root of 9216955981 is about 96004.9789385946. The cubic root of 9216955981 is about 2096.6656064654.

The spelling of 9216955981 in words is "nine billion, two hundred sixteen million, nine hundred fifty-five thousand, nine hundred eighty-one".