1649561 has 8 divisors (see below), whose sum is σ = 1838880. Its totient is φ = 1470528.

The previous prime is 1649539. The next prime is 1649567. The reversal of 1649561 is 1659461.

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

It is a cyclic number.

It is not a de Polignac number, because 1649561 - 2¹⁸ = 1387417 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1649567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2231 + ... + 2876.

It is an arithmetic number, because the mean of its divisors is an integer number (229860).

2^1649561 is an apocalyptic number.

It is an amenable number.

1649561 is a deficient number, since it is larger than the sum of its proper divisors (189319).

1649561 is a wasteful number, since it uses less digits than its factorization.

1649561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5143.

The product of its digits is 6480, while the sum is 32.

The square root of 1649561 is about 1284.3523659806. The cubic root of 1649561 is about 118.1560942937.

The spelling of 1649561 in words is "one million, six hundred forty-nine thousand, five hundred sixty-one".