261485308389 has 16 divisors (see below), whose sum is σ = 358185616640. Its totient is φ = 169557312960.

The previous prime is 261485308333. The next prime is 261485308411. The reversal of 261485308389 is 983803584162.

It is not a de Polignac number, because 261485308389 - 2⁹ = 261485307877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261485308319) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33757 + ... + 723954.

It is an arithmetic number, because the mean of its divisors is an integer number (22386601040).

Almost surely, 2^261485308389 is an apocalyptic number.

It is an amenable number.

261485308389 is a deficient number, since it is larger than the sum of its proper divisors (96700308251).

261485308389 is a wasteful number, since it uses less digits than its factorization.

261485308389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 760860.

The product of its (nonzero) digits is 9953280, while the sum is 57.

The spelling of 261485308389 in words is "two hundred sixty-one billion, four hundred eighty-five million, three hundred eight thousand, three hundred eighty-nine".