1291780164 has 24 divisors (see below), whose sum is σ = 3063567808. Its totient is φ = 423534240.

The previous prime is 1291780163. The next prime is 1291780169. The reversal of 1291780164 is 4610871921.

It is not an unprimeable number, because it can be changed into a prime (1291780163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 881632 + ... + 883095.

Almost surely, 2^1291780164 is an apocalyptic number.

It is an amenable number.

1291780164 is an abundant number, since it is smaller than the sum of its proper divisors (1771787644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1291780164 is a wasteful number, since it uses less digits than its factorization.

1291780164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1764795 (or 1764793 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 1291780164 is about 35941.3433805694. The cubic root of 1291780164 is about 1089.0877432946.

The spelling of 1291780164 in words is "one billion, two hundred ninety-one million, seven hundred eighty thousand, one hundred sixty-four".