261421121434206 has 64 divisors (see below), whose sum is σ = 566089984005120. Its totient is φ = 80201330098560.

The previous prime is 261421121434201. The next prime is 261421121434279. The reversal of 261421121434206 is 602434121124162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261421121434201) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44093526 + ... + 49669721.

It is an arithmetic number, because the mean of its divisors is an integer number (8845156000080).

Almost surely, 2^{261421121434206} is an apocalyptic number.

261421121434206 is an abundant number, since it is smaller than the sum of its proper divisors (304668862570914).

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

261421121434206 is a wasteful number, since it uses less digits than its factorization.

261421121434206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93763969.

The product of its (nonzero) digits is 110592, while the sum is 39.

Adding to 261421121434206 its reverse (602434121124162), we get a palindrome (863855242558368).

The spelling of 261421121434206 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, one hundred twenty-one million, four hundred thirty-four thousand, two hundred six".