61811305 has 4 divisors (see below), whose sum is σ = 74173572. Its totient is φ = 49449040.

The previous prime is 61811297. The next prime is 61811317. The reversal of 61811305 is 50311816.

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 45522009 + 16289296 = 6747^2 + 4036^2 .

It is not a de Polignac number, because 61811305 - 2³ = 61811297 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61811305.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6181126 + ... + 6181135.

It is an arithmetic number, because the mean of its divisors is an integer number (18543393).

Almost surely, 2^61811305 is an apocalyptic number.

It is an amenable number.

61811305 is a deficient number, since it is larger than the sum of its proper divisors (12362267).

61811305 is a wasteful number, since it uses less digits than its factorization.

61811305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12362266.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 61811305 is about 7862.0165988123. The cubic root of 61811305 is about 395.3872290883.

The spelling of 61811305 in words is "sixty-one million, eight hundred eleven thousand, three hundred five".