261550940740 has 24 divisors (see below), whose sum is σ = 558261190872. Its totient is φ = 102905287680.

The previous prime is 261550940683. The next prime is 261550940779. The reversal of 261550940740 is 47049055162.

It can be written as a sum of positive squares in 4 ways, for example, as 59845696 + 261491095044 = 7736^2 + 511362^2 .

It is a super-3 number, since 3×261550940740³ (a number of 35 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107191789 + ... + 107194228.

It is an arithmetic number, because the mean of its divisors is an integer number (23260882953).

Almost surely, 2^261550940740 is an apocalyptic number.

261550940740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261550940740 is an abundant number, since it is smaller than the sum of its proper divisors (296710250132).

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

261550940740 is a wasteful number, since it uses less digits than its factorization.

261550940740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214386087 (or 214386085 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 43.

The spelling of 261550940740 in words is "two hundred sixty-one billion, five hundred fifty million, nine hundred forty thousand, seven hundred forty".