1670390581 has 2 divisors, whose sum is σ = 1670390582. Its totient is φ = 1670390580.

The previous prime is 1670390569. The next prime is 1670390587. The reversal of 1670390581 is 1850930761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1623687025 + 46703556 = 40295^2 + 6834^2 .

It is a cyclic number.

It is not a de Polignac number, because 1670390581 - 2⁵ = 1670390549 is a prime.

It is a super-2 number, since 2×1670390581² = 5580409386187035122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1670390587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835195290 + 835195291.

It is an arithmetic number, because the mean of its divisors is an integer number (835195291).

Almost surely, 2^1670390581 is an apocalyptic number.

It is an amenable number.

1670390581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1670390581 is an equidigital number, since it uses as much as digits as its factorization.

1670390581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 1670390581 is about 40870.4120483266. The cubic root of 1670390581 is about 1186.5134823711.

The spelling of 1670390581 in words is "one billion, six hundred seventy million, three hundred ninety thousand, five hundred eighty-one".