981115409 has 2 divisors, whose sum is σ = 981115410. Its totient is φ = 981115408.

The previous prime is 981115379. The next prime is 981115423. The reversal of 981115409 is 904511189.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 560742400 + 420373009 = 23680^2 + 20503^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-981115409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (981111409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490557704 + 490557705.

It is an arithmetic number, because the mean of its divisors is an integer number (490557705).

Almost surely, 2^981115409 is an apocalyptic number.

It is an amenable number.

981115409 is a deficient number, since it is larger than the sum of its proper divisors (1).

981115409 is an equidigital number, since it uses as much as digits as its factorization.

981115409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 38.

The square root of 981115409 is about 31322.7618354448. The cubic root of 981115409 is about 993.6650899908.

The spelling of 981115409 in words is "nine hundred eighty-one million, one hundred fifteen thousand, four hundred nine".