261690043122 has 24 divisors (see below), whose sum is σ = 567049722876. Its totient is φ = 87221609856.

The previous prime is 261690043051. The next prime is 261690043123. The reversal of 261690043122 is 221340096162.

It is a happy number.

261690043122 is a `hidden beast` number, since 2 + 616 + 9 + 0 + 0 + 4 + 31 + 2 + 2 = 666.

261690043122 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 174647932281 + 87042110841 = 417909^2 + 295029^2 .

It is not an unprimeable number, because it can be changed into a prime (261690043123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 506923 + ... + 883374.

Almost surely, 2^261690043122 is an apocalyptic number.

261690043122 is an abundant number, since it is smaller than the sum of its proper divisors (305359679754).

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

261690043122 is a wasteful number, since it uses less digits than its factorization.

261690043122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1400762 (or 1400759 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The spelling of 261690043122 in words is "two hundred sixty-one billion, six hundred ninety million, forty-three thousand, one hundred twenty-two".