12421780261 has 6 divisors (see below), whose sum is σ = 13653692486. Its totient is φ = 11292527400.

The previous prime is 12421780219. The next prime is 12421780333. The reversal of 12421780261 is 16208712421.

It can be written as a sum of positive squares in only one way, i.e., 10341873025 + 2079907236 = 101695^2 + 45606^2 .

It is not a de Polignac number, because 12421780261 - 2¹⁷ = 12421649189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12421780661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51329550 + ... + 51329791.

Almost surely, 2^12421780261 is an apocalyptic number.

12421780261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12421780261 is a deficient number, since it is larger than the sum of its proper divisors (1231912225).

12421780261 is a wasteful number, since it uses less digits than its factorization.

12421780261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102659363 (or 102659352 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The spelling of 12421780261 in words is "twelve billion, four hundred twenty-one million, seven hundred eighty thousand, two hundred sixty-one".