261121832178828 has 48 divisors (see below), whose sum is σ = 625937049072384. Its totient is φ = 84663038738880.

The previous prime is 261121832178827. The next prime is 261121832178869. The reversal of 261121832178828 is 828871238121162.

261121832178828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×261121832178828² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261121832178827) 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, 85734400 + ... + 88727847.

It is an arithmetic number, because the mean of its divisors is an integer number (13040355189008).

Almost surely, 2^{261121832178828} is an apocalyptic number.

It is an amenable number.

261121832178828 is an abundant number, since it is smaller than the sum of its proper divisors (364815216893556).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261121832178828 is a wasteful number, since it uses less digits than its factorization.

261121832178828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174465662 (or 174465660 counting only the distinct ones).

The product of its digits is 8257536, while the sum is 60.

The spelling of 261121832178828 in words is "two hundred sixty-one trillion, one hundred twenty-one billion, eight hundred thirty-two million, one hundred seventy-eight thousand, eight hundred twenty-eight".