3971820785 has 8 divisors (see below), whose sum is σ = 4770435840. Its totient is φ = 3174622704.

The previous prime is 3971820779. The next prime is 3971820793. The reversal of 3971820785 is 5870281793.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3971820785 - 2¹⁸ = 3971558641 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 348065 + ... + 359294.

It is an arithmetic number, because the mean of its divisors is an integer number (596304480).

Almost surely, 2^3971820785 is an apocalyptic number.

It is an amenable number.

3971820785 is a deficient number, since it is larger than the sum of its proper divisors (798615055).

3971820785 is a wasteful number, since it uses less digits than its factorization.

3971820785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708487.

The product of its (nonzero) digits is 846720, while the sum is 50.

The square root of 3971820785 is about 63022.3832062863. The cubic root of 3971820785 is about 1583.6646210816.

The spelling of 3971820785 in words is "three billion, nine hundred seventy-one million, eight hundred twenty thousand, seven hundred eighty-five".