3853521665781 has 8 divisors (see below), whose sum is σ = 5214715886304. Its totient is φ = 2530670944560.

The previous prime is 3853521665761. The next prime is 3853521665783. The reversal of 3853521665781 is 1875661253583.

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

It is not a de Polignac number, because 3853521665781 - 2³⁴ = 3836341796597 is a prime.

It is a super-2 number, since 2×3853521665781² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3853521665783) 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, 9585874590 + ... + 9585874991.

It is an arithmetic number, because the mean of its divisors is an integer number (651839485788).

Almost surely, 2^{3853521665781} is an apocalyptic number.

It is an amenable number.

3853521665781 is a deficient number, since it is larger than the sum of its proper divisors (1361194220523).

3853521665781 is a wasteful number, since it uses less digits than its factorization.

3853521665781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19171749651.

The product of its digits is 36288000, while the sum is 60.

The spelling of 3853521665781 in words is "three trillion, eight hundred fifty-three billion, five hundred twenty-one million, six hundred sixty-five thousand, seven hundred eighty-one".