820123508 has 6 divisors (see below), whose sum is σ = 1435216146. Its totient is φ = 410061752.

The previous prime is 820123487. The next prime is 820123553. The reversal of 820123508 is 805321028.

It can be written as a sum of positive squares in only one way, i.e., 452327824 + 367795684 = 21268^2 + 19178^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102515435 + ... + 102515442.

It is an arithmetic number, because the mean of its divisors is an integer number (239202691).

Almost surely, 2^820123508 is an apocalyptic number.

It is an amenable number.

820123508 is a deficient number, since it is larger than the sum of its proper divisors (615092638).

820123508 is a wasteful number, since it uses less digits than its factorization.

820123508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205030881 (or 205030879 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 820123508 is about 28637.7985885787. The cubic root of 820123508 is about 936.0371527489.

The spelling of 820123508 in words is "eight hundred twenty million, one hundred twenty-three thousand, five hundred eight".