61447 has 4 divisors (see below), whose sum is σ = 62920. Its totient is φ = 59976.

The previous prime is 61441. The next prime is 61463. The reversal of 61447 is 74416.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61447 - 2¹¹ = 59399 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 672 + ... + 757.

It is an arithmetic number, because the mean of its divisors is an integer number (15730).

2⁶¹⁴⁴⁷ is an apocalyptic number.

61447 is the 133-rd centered heptagonal number.

61447 is a deficient number, since it is larger than the sum of its proper divisors (1473).

61447 is a wasteful number, since it uses less digits than its factorization.

61447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1472.

The product of its digits is 672, while the sum is 22.

The square root of 61447 is about 247.8850540069. The cubic root of 61447 is about 39.4608916987.

Subtracting from 61447 its sum of digits (22), we obtain a triangular number (61425 = T₃₅₀).

The spelling of 61447 in words is "sixty-one thousand, four hundred forty-seven".