261428712625 has 16 divisors (see below), whose sum is σ = 327041769600. Its totient is φ = 208643780400.

The previous prime is 261428712619. The next prime is 261428712667. The reversal of 261428712625 is 526217824162.

It is not a de Polignac number, because 261428712625 - 2³ = 261428712617 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2443365 + ... + 2548114.

It is an arithmetic number, because the mean of its divisors is an integer number (20440110600).

Almost surely, 2^261428712625 is an apocalyptic number.

261428712625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261428712625 is a deficient number, since it is larger than the sum of its proper divisors (65613056975).

261428712625 is an equidigital number, since it uses as much as digits as its factorization.

261428712625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4991913 (or 4991903 counting only the distinct ones).

The product of its digits is 645120, while the sum is 46.

The spelling of 261428712625 in words is "two hundred sixty-one billion, four hundred twenty-eight million, seven hundred twelve thousand, six hundred twenty-five".