61844509 has 4 divisors (see below), whose sum is σ = 61896060. Its totient is φ = 61792960.

The previous prime is 61844483. The next prime is 61844513. The reversal of 61844509 is 90544816.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 54715609 + 7128900 = 7397^2 + 2670^2 .

It is a cyclic number.

It is not a de Polignac number, because 61844509 - 2⁵ = 61844477 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 (61844569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23932 + ... + 26389.

It is an arithmetic number, because the mean of its divisors is an integer number (15474015).

Almost surely, 2^61844509 is an apocalyptic number.

It is an amenable number.

61844509 is a deficient number, since it is larger than the sum of its proper divisors (51551).

61844509 is a wasteful number, since it uses less digits than its factorization.

61844509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51550.

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 61844509 is about 7864.1279872596. The cubic root of 61844509 is about 395.4580148853.

The spelling of 61844509 in words is "sixty-one million, eight hundred forty-four thousand, five hundred nine".