61861109 has 4 divisors (see below), whose sum is σ = 61909260. Its totient is φ = 61812960.

The previous prime is 61861103. The next prime is 61861127. The reversal of 61861109 is 90116816.

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 31114084 + 30747025 = 5578^2 + 5545^2 .

It is a cyclic number.

It is not a de Polignac number, because 61861109 - 2⁸ = 61860853 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61861103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22094 + ... + 24735.

It is an arithmetic number, because the mean of its divisors is an integer number (15477315).

Almost surely, 2^61861109 is an apocalyptic number.

It is an amenable number.

61861109 is a deficient number, since it is larger than the sum of its proper divisors (48151).

61861109 is a wasteful number, since it uses less digits than its factorization.

61861109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48150.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 61861109 is about 7865.1833417918. The cubic root of 61861109 is about 395.4933940207.

The spelling of 61861109 in words is "sixty-one million, eight hundred sixty-one thousand, one hundred nine".