820309972 has 24 divisors (see below), whose sum is σ = 1483069952. Its totient is φ = 396597600.

The previous prime is 820309967. The next prime is 820310033. The reversal of 820309972 is 279903028.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 225238 + ... + 228850.

Almost surely, 2^820309972 is an apocalyptic number.

It is an amenable number.

820309972 is a deficient number, since it is larger than the sum of its proper divisors (662759980).

820309972 is a wasteful number, since it uses less digits than its factorization.

820309972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5479 (or 5477 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 820309972 is about 28641.0539610539. The cubic root of 820309972 is about 936.1080867826.

The spelling of 820309972 in words is "eight hundred twenty million, three hundred nine thousand, nine hundred seventy-two".