2561212365 has 16 divisors (see below), whose sum is σ = 4102612416. Its totient is φ = 1364422400.

The previous prime is 2561212337. The next prime is 2561212387. The reversal of 2561212365 is 5632121652.

It is not a de Polignac number, because 2561212365 - 2⁶ = 2561212301 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 83691 + ... + 110120.

It is an arithmetic number, because the mean of its divisors is an integer number (256413276).

Almost surely, 2^2561212365 is an apocalyptic number.

It is an amenable number.

2561212365 is a deficient number, since it is larger than the sum of its proper divisors (1541400051).

2561212365 is a wasteful number, since it uses less digits than its factorization.

2561212365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194700.

The product of its digits is 21600, while the sum is 33.

The square root of 2561212365 is about 50608.4218781815. The cubic root of 2561212365 is about 1368.1966727385.

The spelling of 2561212365 in words is "two billion, five hundred sixty-one million, two hundred twelve thousand, three hundred sixty-five".