1985223901 has 2 divisors, whose sum is σ = 1985223902. Its totient is φ = 1985223900.

The previous prime is 1985223887. The next prime is 1985223907. The reversal of 1985223901 is 1093225891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1562304676 + 422919225 = 39526^2 + 20565^2 .

It is an emirp because it is prime and its reverse (1093225891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1985223901 - 2⁹ = 1985223389 is a prime.

It is a super-2 number, since 2×1985223901² = 7882227874203315602, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1985223907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 992611950 + 992611951.

It is an arithmetic number, because the mean of its divisors is an integer number (992611951).

Almost surely, 2^1985223901 is an apocalyptic number.

It is an amenable number.

1985223901 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985223901 is an equidigital number, since it uses as much as digits as its factorization.

1985223901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 1985223901 is about 44555.8514787901. The cubic root of 1985223901 is about 1256.8105908359.

The spelling of 1985223901 in words is "one billion, nine hundred eighty-five million, two hundred twenty-three thousand, nine hundred one".