1261422413 has 4 divisors (see below), whose sum is σ = 1261499580. Its totient is φ = 1261345248.

The previous prime is 1261422403. The next prime is 1261422433. The reversal of 1261422413 is 3142241621.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3142241621 = 2357 ⋅1333153.

It can be written as a sum of positive squares in 2 ways, for example, as 1134477124 + 126945289 = 33682^2 + 11267^2 .

It is a cyclic number.

It is not a de Polignac number, because 1261422413 - 2⁴ = 1261422397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261422403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3320 + ... + 50337.

It is an arithmetic number, because the mean of its divisors is an integer number (315374895).

Almost surely, 2^1261422413 is an apocalyptic number.

It is an amenable number.

1261422413 is a deficient number, since it is larger than the sum of its proper divisors (77167).

1261422413 is an equidigital number, since it uses as much as digits as its factorization.

1261422413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77166.

The product of its digits is 2304, while the sum is 26.

The square root of 1261422413 is about 35516.5090204541. The cubic root of 1261422413 is about 1080.4885800930.

The spelling of 1261422413 in words is "one billion, two hundred sixty-one million, four hundred twenty-two thousand, four hundred thirteen".