1291198725 has 72 divisors (see below), whose sum is σ = 2502881472. Its totient is φ = 658627200.

The previous prime is 1291198663. The next prime is 1291198759. The reversal of 1291198725 is 5278911921.

It is not a de Polignac number, because 1291198725 - 2¹² = 1291194629 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 71 ways as a sum of consecutive naturals, for example, 135105 + ... + 144345.

Almost surely, 2^1291198725 is an apocalyptic number.

1291198725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1291198725 is a deficient number, since it is larger than the sum of its proper divisors (1211682747).

1291198725 is an equidigital number, since it uses as much as digits as its factorization.

1291198725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9289 (or 9272 counting only the distinct ones).

The product of its digits is 90720, while the sum is 45.

The square root of 1291198725 is about 35933.2537491388. The cubic root of 1291198725 is about 1088.9243168495.

The spelling of 1291198725 in words is "one billion, two hundred ninety-one million, one hundred ninety-eight thousand, seven hundred twenty-five".