1261672807 has 4 divisors (see below), whose sum is σ = 1262113920. Its totient is φ = 1261231696.

The previous prime is 1261672759. The next prime is 1261672817. The reversal of 1261672807 is 7082761621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7082761621 = 13 ⋅544827817.

It is a cyclic number.

It is not a de Polignac number, because 1261672807 - 2⁷ = 1261672679 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1261672807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261672817) 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 3 ways as a sum of consecutive naturals, for example, 216238 + ... + 221995.

It is an arithmetic number, because the mean of its divisors is an integer number (315528480).

Almost surely, 2^1261672807 is an apocalyptic number.

1261672807 is a deficient number, since it is larger than the sum of its proper divisors (441113).

1261672807 is an equidigital number, since it uses as much as digits as its factorization.

1261672807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441112.

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 1261672807 is about 35520.0338823037. The cubic root of 1261672807 is about 1080.5600681621.

The spelling of 1261672807 in words is "one billion, two hundred sixty-one million, six hundred seventy-two thousand, eight hundred seven".