8143251821 has 16 divisors (see below), whose sum is σ = 9011461248. Its totient is φ = 7319347200.

The previous prime is 8143251773. The next prime is 8143251839. The reversal of 8143251821 is 1281523418.

It is a cyclic number.

It is not a de Polignac number, because 8143251821 - 2¹⁸ = 8142989677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8143251841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234386 + ... + 266876.

It is an arithmetic number, because the mean of its divisors is an integer number (563216328).

Almost surely, 2^8143251821 is an apocalyptic number.

It is an amenable number.

8143251821 is a deficient number, since it is larger than the sum of its proper divisors (868209427).

8143251821 is a wasteful number, since it uses less digits than its factorization.

8143251821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33172.

The product of its digits is 15360, while the sum is 35.

The square root of 8143251821 is about 90239.9679798259. The cubic root of 8143251821 is about 2011.8670984686.

The spelling of 8143251821 in words is "eight billion, one hundred forty-three million, two hundred fifty-one thousand, eight hundred twenty-one".