1291664888 has 8 divisors (see below), whose sum is σ = 2421871680. Its totient is φ = 645832440.

The previous prime is 1291664887. The next prime is 1291664893. The reversal of 1291664888 is 8884661921.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291664887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80729048 + ... + 80729063.

It is an arithmetic number, because the mean of its divisors is an integer number (302733960).

Almost surely, 2^1291664888 is an apocalyptic number.

It is an amenable number.

1291664888 is a deficient number, since it is larger than the sum of its proper divisors (1130206792).

1291664888 is a wasteful number, since it uses less digits than its factorization.

1291664888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161458117 (or 161458113 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 53.

The square root of 1291664888 is about 35939.7396762970. The cubic root of 1291664888 is about 1089.0553462927.

The spelling of 1291664888 in words is "one billion, two hundred ninety-one million, six hundred sixty-four thousand, eight hundred eighty-eight".