1275105491 has 4 divisors (see below), whose sum is σ = 1391024184. Its totient is φ = 1159186800.

The previous prime is 1275105473. The next prime is 1275105493. The reversal of 1275105491 is 1945015721.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1945015721 = 11 ⋅176819611.

It is a cyclic number.

It is not a de Polignac number, because 1275105491 - 2¹⁸ = 1274843347 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1275105493) 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, 57959330 + ... + 57959351.

It is an arithmetic number, because the mean of its divisors is an integer number (347756046).

Almost surely, 2^1275105491 is an apocalyptic number.

1275105491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1275105491 is a deficient number, since it is larger than the sum of its proper divisors (115918693).

1275105491 is a wasteful number, since it uses less digits than its factorization.

1275105491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115918692.

The product of its (nonzero) digits is 12600, while the sum is 35.

The square root of 1275105491 is about 35708.6192816244. The cubic root of 1275105491 is about 1084.3813475044.

The spelling of 1275105491 in words is "one billion, two hundred seventy-five million, one hundred five thousand, four hundred ninety-one".