17878961 has 2 divisors, whose sum is σ = 17878962. Its totient is φ = 17878960.

The previous prime is 17878901. The next prime is 17878969. The reversal of 17878961 is 16987871.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14868736 + 3010225 = 3856^2 + 1735^2 .

It is a cyclic number.

It is not a de Polignac number, because 17878961 - 2¹⁴ = 17862577 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (17878969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8939480 + 8939481.

It is an arithmetic number, because the mean of its divisors is an integer number (8939481).

Almost surely, 2^17878961 is an apocalyptic number.

It is an amenable number.

17878961 is a deficient number, since it is larger than the sum of its proper divisors (1).

17878961 is an equidigital number, since it uses as much as digits as its factorization.

17878961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 169344, while the sum is 47.

The square root of 17878961 is about 4228.3520430541. The cubic root of 17878961 is about 261.4853883014.

The spelling of 17878961 in words is "seventeen million, eight hundred seventy-eight thousand, nine hundred sixty-one".