831421305 has 96 divisors (see below), whose sum is σ = 1729728000. Its totient is φ = 364055040.

The previous prime is 831421303. The next prime is 831421421. The reversal of 831421305 is 503124138.

It is a happy number.

It is not a de Polignac number, because 831421305 - 2¹ = 831421303 is a prime.

It is a super-2 number, since 2×831421305² = 1382522772815806050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (831421303) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 301071 + ... + 303819.

It is an arithmetic number, because the mean of its divisors is an integer number (18018000).

Almost surely, 2^831421305 is an apocalyptic number.

It is an amenable number.

831421305 is an abundant number, since it is smaller than the sum of its proper divisors (898306695).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

831421305 is a wasteful number, since it uses less digits than its factorization.

831421305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2831 (or 2828 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 831421305 is about 28834.3771391026. The cubic root of 831421305 is about 940.3157627121.

The spelling of 831421305 in words is "eight hundred thirty-one million, four hundred twenty-one thousand, three hundred five".