261409529520 has 60 divisors (see below), whose sum is σ = 877900339056. Its totient is φ = 69709207680.

The previous prime is 261409529519. The next prime is 261409529543. The reversal of 261409529520 is 25925904162.

261409529520 is a `hidden beast` number, since 2 + 6 + 14 + 0 + 95 + 29 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181533676 + ... + 181535115.

Almost surely, 2^261409529520 is an apocalyptic number.

261409529520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261409529520 is an abundant number, since it is smaller than the sum of its proper divisors (616490809536).

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

261409529520 is a wasteful number, since it uses less digits than its factorization.

261409529520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363068810 (or 363068801 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 261409529520 in words is "two hundred sixty-one billion, four hundred nine million, five hundred twenty-nine thousand, five hundred twenty".