1985199613 has 2 divisors, whose sum is σ = 1985199614. Its totient is φ = 1985199612.

The previous prime is 1985199589. The next prime is 1985199617. The reversal of 1985199613 is 3169915891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1031501689 + 953697924 = 32117^2 + 30882^2 .

It is a cyclic number.

It is not a de Polignac number, because 1985199613 - 2⁹ = 1985199101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1985199617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 992599806 + 992599807.

It is an arithmetic number, because the mean of its divisors is an integer number (992599807).

Almost surely, 2^1985199613 is an apocalyptic number.

It is an amenable number.

1985199613 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985199613 is an equidigital number, since it uses as much as digits as its factorization.

1985199613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 524880, while the sum is 52.

The square root of 1985199613 is about 44555.5789211632. The cubic root of 1985199613 is about 1256.8054653788.

The spelling of 1985199613 in words is "one billion, nine hundred eighty-five million, one hundred ninety-nine thousand, six hundred thirteen".