1291215825 has 72 divisors (see below), whose sum is σ = 2431128128. Its totient is φ = 654272640.

The previous prime is 1291215817. The next prime is 1291215847. The reversal of 1291215825 is 5285121921.

It is not a de Polignac number, because 1291215825 - 2³ = 1291215817 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 1291215825.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 356172 + ... + 359778.

Almost surely, 2^1291215825 is an apocalyptic number.

1291215825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1291215825 is a deficient number, since it is larger than the sum of its proper divisors (1139912303).

1291215825 is a wasteful number, since it uses less digits than its factorization.

1291215825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3703 (or 3695 counting only the distinct ones).

The product of its digits is 14400, while the sum is 36.

The square root of 1291215825 is about 35933.4916895088. The cubic root of 1291215825 is about 1088.9291238874.

The spelling of 1291215825 in words is "one billion, two hundred ninety-one million, two hundred fifteen thousand, eight hundred twenty-five".