1261871453 has 4 divisors (see below), whose sum is σ = 1328285760. Its totient is φ = 1195457148.

The previous prime is 1261871449. The next prime is 1261871489. The reversal of 1261871453 is 3541781621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1261871453 - 2² = 1261871449 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 (1261871953) 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, 33207125 + ... + 33207162.

It is an arithmetic number, because the mean of its divisors is an integer number (332071440).

Almost surely, 2^1261871453 is an apocalyptic number.

It is an amenable number.

1261871453 is a deficient number, since it is larger than the sum of its proper divisors (66414307).

1261871453 is an equidigital number, since it uses as much as digits as its factorization.

1261871453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66414306.

The product of its digits is 40320, while the sum is 38.

The square root of 1261871453 is about 35522.8300252105. The cubic root of 1261871453 is about 1080.6167753290.

The spelling of 1261871453 in words is "one billion, two hundred sixty-one million, eight hundred seventy-one thousand, four hundred fifty-three".