1209551667 has 4 divisors (see below), whose sum is σ = 1612735560. Its totient is φ = 806367776.

The previous prime is 1209551663. The next prime is 1209551731. The reversal of 1209551667 is 7661559021.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1209551667 - 2² = 1209551663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1209551663) 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, 201591942 + ... + 201591947.

It is an arithmetic number, because the mean of its divisors is an integer number (403183890).

Almost surely, 2^1209551667 is an apocalyptic number.

1209551667 is a deficient number, since it is larger than the sum of its proper divisors (403183893).

1209551667 is an equidigital number, since it uses as much as digits as its factorization.

1209551667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403183892.

The product of its (nonzero) digits is 113400, while the sum is 42.

The square root of 1209551667 is about 34778.6093310241. The cubic root of 1209551667 is about 1065.4706104126.

The spelling of 1209551667 in words is "one billion, two hundred nine million, five hundred fifty-one thousand, six hundred sixty-seven".