8421691231 has 2 divisors, whose sum is σ = 8421691232. Its totient is φ = 8421691230.

The previous prime is 8421691219. The next prime is 8421691259. The reversal of 8421691231 is 1321961248.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 8421691231 - 2²⁹ = 7884820319 is a prime.

It is a super-2 number, since 2×8421691231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8421691331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4210845615 + 4210845616.

It is an arithmetic number, because the mean of its divisors is an integer number (4210845616).

Almost surely, 2^8421691231 is an apocalyptic number.

8421691231 is a deficient number, since it is larger than the sum of its proper divisors (1).

8421691231 is an equidigital number, since it uses as much as digits as its factorization.

8421691231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 8421691231 is about 91769.7729701888. The cubic root of 8421691231 is about 2034.5409626926.

The spelling of 8421691231 in words is "eight billion, four hundred twenty-one million, six hundred ninety-one thousand, two hundred thirty-one".