820280331 has 64 divisors (see below), whose sum is σ = 1407436800. Its totient is φ = 467866368.

The previous prime is 820280327. The next prime is 820280347. The reversal of 820280331 is 133082028.

It is not a de Polignac number, because 820280331 - 2² = 820280327 is a prime.

It is a super-2 number, since 2×820280331² = 1345719642850939122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 820280295 and 820280304.

It is not an unprimeable number, because it can be changed into a prime (820280371) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 312135 + ... + 314751.

It is an arithmetic number, because the mean of its divisors is an integer number (21991200).

Almost surely, 2^820280331 is an apocalyptic number.

820280331 is a deficient number, since it is larger than the sum of its proper divisors (587156469).

820280331 is a wasteful number, since it uses less digits than its factorization.

820280331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2705 (or 2699 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 820280331 is about 28640.5364998633. The cubic root of 820280331 is about 936.0968115675.

The spelling of 820280331 in words is "eight hundred twenty million, two hundred eighty thousand, three hundred thirty-one".