661269 has 8 divisors (see below), whose sum is σ = 1007680. Its totient is φ = 377856.

The previous prime is 661267. The next prime is 661321. The reversal of 661269 is 962166.

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

It is not a de Polignac number, because 661269 - 2¹ = 661267 is a prime.

It is a super-2 number, since 2×661269² = 874553380722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661267) 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, 15724 + ... + 15765.

It is an arithmetic number, because the mean of its divisors is an integer number (125960).

2⁶⁶¹²⁶⁹ is an apocalyptic number.

It is an amenable number.

661269 is a deficient number, since it is larger than the sum of its proper divisors (346411).

661269 is a wasteful number, since it uses less digits than its factorization.

661269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31499.

The product of its digits is 3888, while the sum is 30.

The square root of 661269 is about 813.1844809144. The cubic root of 661269 is about 87.1216424983.

The spelling of 661269 in words is "six hundred sixty-one thousand, two hundred sixty-nine".