1291653899 has 4 divisors (see below), whose sum is σ = 1293663336. Its totient is φ = 1289644464.

The previous prime is 1291653893. The next prime is 1291653911. The reversal of 1291653899 is 9983561921.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1291653899 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 1291653899.

It is not an unprimeable number, because it can be changed into a prime (1291653893) 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, 1003754 + ... + 1005039.

It is an arithmetic number, because the mean of its divisors is an integer number (323415834).

Almost surely, 2^1291653899 is an apocalyptic number.

1291653899 is a deficient number, since it is larger than the sum of its proper divisors (2009437).

1291653899 is an equidigital number, since it uses as much as digits as its factorization.

1291653899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009436.

The product of its digits is 1049760, while the sum is 53.

The square root of 1291653899 is about 35939.5867950649. The cubic root of 1291653899 is about 1089.0522578592.

The spelling of 1291653899 in words is "one billion, two hundred ninety-one million, six hundred fifty-three thousand, eight hundred ninety-nine".