90197839 has 2 divisors, whose sum is σ = 90197840. Its totient is φ = 90197838.

The previous prime is 90197803. The next prime is 90197867. The reversal of 90197839 is 93879109.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90197839 - 2¹⁵ = 90165071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90197339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45098919 + 45098920.

It is an arithmetic number, because the mean of its divisors is an integer number (45098920).

Almost surely, 2^90197839 is an apocalyptic number.

90197839 is a deficient number, since it is larger than the sum of its proper divisors (1).

90197839 is an equidigital number, since it uses as much as digits as its factorization.

90197839 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 90197839 is about 9497.2542874243. The cubic root of 90197839 is about 448.4686034645.

The spelling of 90197839 in words is "ninety million, one hundred ninety-seven thousand, eight hundred thirty-nine".