1661613 has 16 divisors (see below), whose sum is σ = 2332800. Its totient is φ = 1050560.

The previous prime is 1661599. The next prime is 1661623. The reversal of 1661613 is 3161661.

It is a cyclic number.

It is not a de Polignac number, because 1661613 - 2⁶ = 1661549 is a prime.

It is an Ulam number.

1661613 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6043 + ... + 6311.

It is an arithmetic number, because the mean of its divisors is an integer number (145800).

2^1661613 is an apocalyptic number.

It is an amenable number.

1661613 is a deficient number, since it is larger than the sum of its proper divisors (671187).

1661613 is a wasteful number, since it uses less digits than its factorization.

1661613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372.

The product of its digits is 648, while the sum is 24.

The square root of 1661613 is about 1289.0356860848. The cubic root of 1661613 is about 118.4431531358.

The spelling of 1661613 in words is "one million, six hundred sixty-one thousand, six hundred thirteen".