42856461806261 has 4 divisors (see below), whose sum is σ = 42856631937132. Its totient is φ = 42856291675392.

The previous prime is 42856461806251. The next prime is 42856461806267. The reversal of 42856461806261 is 16260816465824.

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 27752403483025 + 15104058323236 = 5268055^2 + 3886394^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42856461806261 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 42856461806261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42856461806267) 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, 84687020 + ... + 85191573.

It is an arithmetic number, because the mean of its divisors is an integer number (10714157984283).

Almost surely, 2^{42856461806261} is an apocalyptic number.

It is an amenable number.

42856461806261 is a deficient number, since it is larger than the sum of its proper divisors (170130871).

42856461806261 is a wasteful number, since it uses less digits than its factorization.

42856461806261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170130870.

The product of its (nonzero) digits is 26542080, while the sum is 59.

The spelling of 42856461806261 in words is "forty-two trillion, eight hundred fifty-six billion, four hundred sixty-one million, eight hundred six thousand, two hundred sixty-one".