1690661 has 8 divisors (see below), whose sum is σ = 2016384. Its totient is φ = 1386000.

The previous prime is 1690651. The next prime is 1690669. The reversal of 1690661 is 1660961.

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

It is not a de Polignac number, because 1690661 - 2⁶ = 1690597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1690669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5090 + ... + 5411.

It is an arithmetic number, because the mean of its divisors is an integer number (252048).

2^1690661 is an apocalyptic number.

It is an amenable number.

1690661 is a deficient number, since it is larger than the sum of its proper divisors (325723).

1690661 is a wasteful number, since it uses less digits than its factorization.

1690661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10531.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 1690661 is about 1300.2542059151. The cubic root of 1690661 is about 119.1293699333.

The spelling of 1690661 in words is "one million, six hundred ninety thousand, six hundred sixty-one".