261020856307 has 12 divisors (see below), whose sum is σ = 270449172136. Its totient is φ = 251910852480.

The previous prime is 261020856281. The next prime is 261020856347. The reversal of 261020856307 is 703658020162.

It is not a de Polignac number, because 261020856307 - 2⁷ = 261020856179 is a prime.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

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 261020856307.

It is not an unprimeable number, because it can be changed into a prime (261020856347) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1907707 + ... + 2039947.

Almost surely, 2^261020856307 is an apocalyptic number.

261020856307 is a deficient number, since it is larger than the sum of its proper divisors (9428315829).

261020856307 is a wasteful number, since it uses less digits than its factorization.

261020856307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134646 (or 134617 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

Adding to 261020856307 its reverse (703658020162), we get a palindrome (964678876469).

The spelling of 261020856307 in words is "two hundred sixty-one billion, twenty million, eight hundred fifty-six thousand, three hundred seven".