1670981 has 8 divisors (see below), whose sum is σ = 1905624. Its totient is φ = 1451520.

The previous prime is 1670971. The next prime is 1670983. The reversal of 1670981 is 1890761.

It can be written as a sum of positive squares in 4 ways, for example, as 70756 + 1600225 = 266^2 + 1265^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1670981 is a prime.

It is a super-2 number, since 2×1670981² = 5584355004722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1670983) 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, 3560 + ... + 4001.

It is an arithmetic number, because the mean of its divisors is an integer number (238203).

2^1670981 is an apocalyptic number.

It is an amenable number.

1670981 is a deficient number, since it is larger than the sum of its proper divisors (234643).

1670981 is a wasteful number, since it uses less digits than its factorization.

1670981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7591.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 1670981 is about 1292.6643029031. The cubic root of 1670981 is about 118.6653261572.

The spelling of 1670981 in words is "one million, six hundred seventy thousand, nine hundred eighty-one".