9942977744981 has 2 divisors, whose sum is σ = 9942977744982. Its totient is φ = 9942977744980.

The previous prime is 9942977744971. The next prime is 9942977745047. The reversal of 9942977744981 is 1894477792499.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8543145653956 + 1399832091025 = 2922866^2 + 1183145^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9942977744981 is a prime.

It is a super-2 number, since 2×9942977744981² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 9942977744896 and 9942977744905.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9942977744941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4971488872490 + 4971488872491.

It is an arithmetic number, because the mean of its divisors is an integer number (4971488872491).

Almost surely, 2^{9942977744981} is an apocalyptic number.

It is an amenable number.

9942977744981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9942977744981 is an equidigital number, since it uses as much as digits as its factorization.

9942977744981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304433152, while the sum is 80.

The spelling of 9942977744981 in words is "nine trillion, nine hundred forty-two billion, nine hundred seventy-seven million, seven hundred forty-four thousand, nine hundred eighty-one".