661461 has 8 divisors (see below), whose sum is σ = 912480. Its totient is φ = 425712.

The previous prime is 661459. The next prime is 661477. The reversal of 661461 is 164166.

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

It is not a de Polignac number, because 661461 - 2¹ = 661459 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661421) 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, 3715 + ... + 3888.

It is an arithmetic number, because the mean of its divisors is an integer number (114060).

2⁶⁶¹⁴⁶¹ is an apocalyptic number.

It is an amenable number.

661461 is a deficient number, since it is larger than the sum of its proper divisors (251019).

661461 is a wasteful number, since it uses less digits than its factorization.

661461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7635.

The product of its digits is 864, while the sum is 24.

The square root of 661461 is about 813.3025267390. The cubic root of 661461 is about 87.1300736293.

The spelling of 661461 in words is "six hundred sixty-one thousand, four hundred sixty-one".