3948757821 has 24 divisors (see below), whose sum is σ = 6006549120. Its totient is φ = 2492876736.

The previous prime is 3948757801. The next prime is 3948757823. The reversal of 3948757821 is 1287578493.

It is a happy number.

3948757821 is a `hidden beast` number, since 3 + 9 + 48 + 7 + 578 + 21 = 666.

It is not a de Polignac number, because 3948757821 - 2¹⁷ = 3948626749 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3948757823) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 624940 + ... + 631226.

It is an arithmetic number, because the mean of its divisors is an integer number (250272880).

Almost surely, 2^3948757821 is an apocalyptic number.

It is an amenable number.

3948757821 is a deficient number, since it is larger than the sum of its proper divisors (2057791299).

3948757821 is a wasteful number, since it uses less digits than its factorization.

3948757821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9985 (or 9982 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The square root of 3948757821 is about 62839.1424273120. The cubic root of 3948757821 is about 1580.5934080649.

The spelling of 3948757821 in words is "three billion, nine hundred forty-eight million, seven hundred fifty-seven thousand, eight hundred twenty-one".