1261662361 has 8 divisors (see below), whose sum is σ = 1336206024. Its totient is φ = 1187155200.

The previous prime is 1261662349. The next prime is 1261662383. The reversal of 1261662361 is 1632661621.

It can be written as a sum of positive squares in 4 ways, for example, as 1118501136 + 143161225 = 33444^2 + 11965^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1261662361 - 2¹⁷ = 1261531289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1261662331) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98211 + ... + 110311.

It is an arithmetic number, because the mean of its divisors is an integer number (167025753).

Almost surely, 2^1261662361 is an apocalyptic number.

It is an amenable number.

1261662361 is a deficient number, since it is larger than the sum of its proper divisors (74543663).

1261662361 is a wasteful number, since it uses less digits than its factorization.

1261662361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18251.

The product of its digits is 15552, while the sum is 34.

The square root of 1261662361 is about 35519.8868382206. The cubic root of 1261662361 is about 1080.5570859939.

The spelling of 1261662361 in words is "one billion, two hundred sixty-one million, six hundred sixty-two thousand, three hundred sixty-one".