661829 has 4 divisors (see below), whose sum is σ = 756384. Its totient is φ = 567276.

The previous prime is 661823. The next prime is 661849. The reversal of 661829 is 928166.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 661829 - 2¹⁶ = 596293 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 661795 and 661804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47267 + ... + 47280.

It is an arithmetic number, because the mean of its divisors is an integer number (189096).

2⁶⁶¹⁸²⁹ is an apocalyptic number.

It is an amenable number.

661829 is a deficient number, since it is larger than the sum of its proper divisors (94555).

661829 is an equidigital number, since it uses as much as digits as its factorization.

661829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94554.

The product of its digits is 5184, while the sum is 32.

The square root of 661829 is about 813.5287333586. The cubic root of 661829 is about 87.1462287379.

The spelling of 661829 in words is "six hundred sixty-one thousand, eight hundred twenty-nine".