1630720831 has 2 divisors, whose sum is σ = 1630720832. Its totient is φ = 1630720830.

The previous prime is 1630720813. The next prime is 1630720859. The reversal of 1630720831 is 1380270361.

Together with previous prime (1630720813) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1630720831 - 2⁷ = 1630720703 is a prime.

It is a super-2 number, since 2×1630720831² = 5318500857314661122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1630720793 and 1630720802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1630720811) by changing a digit.

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 as a sum of consecutive naturals, namely, 815360415 + 815360416.

It is an arithmetic number, because the mean of its divisors is an integer number (815360416).

Almost surely, 2^1630720831 is an apocalyptic number.

1630720831 is a deficient number, since it is larger than the sum of its proper divisors (1).

1630720831 is an equidigital number, since it uses as much as digits as its factorization.

1630720831 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 1630720831 is about 40382.1845743887. The cubic root of 1630720831 is about 1177.0453780844.

The spelling of 1630720831 in words is "one billion, six hundred thirty million, seven hundred twenty thousand, eight hundred thirty-one".