17970991 has 2 divisors, whose sum is σ = 17970992. Its totient is φ = 17970990.

The previous prime is 17970977. The next prime is 17971001. The reversal of 17970991 is 19907971.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 17970991 - 2¹³ = 17962799 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17971991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8985495 + 8985496.

It is an arithmetic number, because the mean of its divisors is an integer number (8985496).

Almost surely, 2^17970991 is an apocalyptic number.

17970991 is a deficient number, since it is larger than the sum of its proper divisors (1).

17970991 is an equidigital number, since it uses as much as digits as its factorization.

17970991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 35721, while the sum is 43.

The square root of 17970991 is about 4239.2205651511. The cubic root of 17970991 is about 261.9332765234.

The spelling of 17970991 in words is "seventeen million, nine hundred seventy thousand, nine hundred ninety-one".