61641 has 10 divisors (see below), whose sum is σ = 92202. Its totient is φ = 41040.

The previous prime is 61637. The next prime is 61643. The reversal of 61641 is 14616.

61641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 32400 + 29241 = 180^2 + 171^2 .

It is not a de Polignac number, because 61641 - 2² = 61637 is a prime.

It is a super-2 number, since 2×61641² = 7599225762, which contains 22 as substring.

It is a plaindrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61643) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 300 + ... + 461.

2⁶¹⁶⁴¹ is an apocalyptic number.

It is an amenable number.

61641 is a deficient number, since it is larger than the sum of its proper divisors (30561).

61641 is an equidigital number, since it uses as much as digits as its factorization.

61641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773 (or 764 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 61641 is about 248.2760560344. The cubic root of 61641 is about 39.5023766129.

The spelling of 61641 in words is "sixty-one thousand, six hundred forty-one".