61945 has 8 divisors (see below), whose sum is σ = 80136. Its totient is φ = 45696.

The previous prime is 61933. The next prime is 61949. The reversal of 61945 is 54916.

It can be written as a sum of positive squares in 4 ways, for example, as 441 + 61504 = 21^2 + 248^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61945 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61949) 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, 412 + ... + 541.

It is an arithmetic number, because the mean of its divisors is an integer number (10017).

2⁶¹⁹⁴⁵ is an apocalyptic number.

61945 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

61945 is a deficient number, since it is larger than the sum of its proper divisors (18191).

61945 is a wasteful number, since it uses less digits than its factorization.

61945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971.

The product of its digits is 1080, while the sum is 25.

The square root of 61945 is about 248.8875247978. The cubic root of 61945 is about 39.5672091915.

The spelling of 61945 in words is "sixty-one thousand, nine hundred forty-five".