1670647561 has 8 divisors (see below), whose sum is σ = 1918447200. Its totient is φ = 1438835040.

The previous prime is 1670647553. The next prime is 1670647597. The reversal of 1670647561 is 1657460761.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1670647561 - 2³ = 1670647553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1670647501) 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 in 7 ways as a sum of consecutive naturals, for example, 3996556 + ... + 3996973.

It is an arithmetic number, because the mean of its divisors is an integer number (239805900).

Almost surely, 2^1670647561 is an apocalyptic number.

1670647561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1670647561 is a deficient number, since it is larger than the sum of its proper divisors (247799639).

1670647561 is a wasteful number, since it uses less digits than its factorization.

1670647561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7993559.

The product of its (nonzero) digits is 211680, while the sum is 43.

The square root of 1670647561 is about 40873.5557665344. Note that the first 3 decimals coincide. The cubic root of 1670647561 is about 1186.5743253466.

The spelling of 1670647561 in words is "one billion, six hundred seventy million, six hundred forty-seven thousand, five hundred sixty-one".