196991539 has 2 divisors, whose sum is σ = 196991540. Its totient is φ = 196991538.

The previous prime is 196991537. The next prime is 196991549. The reversal of 196991539 is 935199691.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 196991539 - 2¹ = 196991537 is a prime.

Together with 196991537, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (196991537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98495769 + 98495770.

It is an arithmetic number, because the mean of its divisors is an integer number (98495770).

Almost surely, 2^196991539 is an apocalyptic number.

196991539 is a deficient number, since it is larger than the sum of its proper divisors (1).

196991539 is an equidigital number, since it uses as much as digits as its factorization.

196991539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 590490, while the sum is 52.

The square root of 196991539 is about 14035.3674337368. The cubic root of 196991539 is about 581.8564564139.

The spelling of 196991539 in words is "one hundred ninety-six million, nine hundred ninety-one thousand, five hundred thirty-nine".