261407994480 has 60 divisors (see below), whose sum is σ = 877895183880. Its totient is φ = 69708798336.

The previous prime is 261407994437. The next prime is 261407994493. The reversal of 261407994480 is 84499704162.

261407994480 is a `hidden beast` number, since 2 + 6 + 1 + 4 + 0 + 79 + 94 + 480 = 666.

261407994480 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181532610 + ... + 181534049.

It is an arithmetic number, because the mean of its divisors is an integer number (14631586398).

Almost surely, 2^261407994480 is an apocalyptic number.

261407994480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261407994480 is an abundant number, since it is smaller than the sum of its proper divisors (616487189400).

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

261407994480 is a wasteful number, since it uses less digits than its factorization.

261407994480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363066678 (or 363066669 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 54.

The spelling of 261407994480 in words is "two hundred sixty-one billion, four hundred seven million, nine hundred ninety-four thousand, four hundred eighty".