1985840450947 has 2 divisors, whose sum is σ = 1985840450948. Its totient is φ = 1985840450946.

The previous prime is 1985840450927. The next prime is 1985840451019. The reversal of 1985840450947 is 7490540485891.

It is a weak prime.

It is an emirp because it is prime and its reverse (7490540485891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1985840450947 - 2³¹ = 1983692967299 is a prime.

It is not a weakly prime, because it can be changed into another prime (1985840450917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 992920225473 + 992920225474.

It is an arithmetic number, because the mean of its divisors is an integer number (992920225474).

Almost surely, 2^{1985840450947} is an apocalyptic number.

1985840450947 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985840450947 is an equidigital number, since it uses as much as digits as its factorization.

1985840450947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58060800, while the sum is 64.

The spelling of 1985840450947 in words is "one trillion, nine hundred eighty-five billion, eight hundred forty million, four hundred fifty thousand, nine hundred forty-seven".