1261294947 has 12 divisors (see below), whose sum is σ = 1987495224. Its totient is φ = 764421120.

The previous prime is 1261294943. The next prime is 1261295003. The reversal of 1261294947 is 7494921621.

It is not a de Polignac number, because 1261294947 - 2² = 1261294943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1261294943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6370078 + ... + 6370275.

It is an arithmetic number, because the mean of its divisors is an integer number (165624602).

Almost surely, 2^1261294947 is an apocalyptic number.

1261294947 is a deficient number, since it is larger than the sum of its proper divisors (726200277).

1261294947 is a wasteful number, since it uses less digits than its factorization.

1261294947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12740370 (or 12740367 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 1261294947 is about 35514.7145138462. The cubic root of 1261294947 is about 1080.4521846198.

The spelling of 1261294947 in words is "one billion, two hundred sixty-one million, two hundred ninety-four thousand, nine hundred forty-seven".