3861863553821 has 8 divisors (see below), whose sum is σ = 4753062835584. Its totient is φ = 3055540394160.

The previous prime is 3861863553787. The next prime is 3861863553839. The reversal of 3861863553821 is 1283553681683.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3861863553821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3861863553841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21219030425 + ... + 21219030606.

It is an arithmetic number, because the mean of its divisors is an integer number (594132854448).

Almost surely, 2^{3861863553821} is an apocalyptic number.

It is an amenable number.

3861863553821 is a deficient number, since it is larger than the sum of its proper divisors (891199281763).

3861863553821 is a wasteful number, since it uses less digits than its factorization.

3861863553821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42438061051.

The product of its digits is 24883200, while the sum is 59.

The spelling of 3861863553821 in words is "three trillion, eight hundred sixty-one billion, eight hundred sixty-three million, five hundred fifty-three thousand, eight hundred twenty-one".