61256550605 has 4 divisors (see below), whose sum is σ = 73507860732. Its totient is φ = 49005240480.

The previous prime is 61256550587. The next prime is 61256550631. The reversal of 61256550605 is 50605565216.

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 23619386596 + 37637164009 = 153686^2 + 194003^2 .

It is not a de Polignac number, because 61256550605 - 2¹⁴ = 61256534221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6125655056 + ... + 6125655065.

It is an arithmetic number, because the mean of its divisors is an integer number (18376965183).

Almost surely, 2^61256550605 is an apocalyptic number.

It is an amenable number.

61256550605 is a deficient number, since it is larger than the sum of its proper divisors (12251310127).

61256550605 is a wasteful number, since it uses less digits than its factorization.

61256550605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12251310126.

The product of its (nonzero) digits is 270000, while the sum is 41.

The spelling of 61256550605 in words is "sixty-one billion, two hundred fifty-six million, five hundred fifty thousand, six hundred five".