1291650428 has 12 divisors (see below), whose sum is σ = 2308481952. Its totient is φ = 632084160.

The previous prime is 1291650421. The next prime is 1291650431. The reversal of 1291650428 is 8240561921.

It is a junction number, because it is equal to n+sod(n) for n = 1291650391 and 1291650400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291650421) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3435053 + ... + 3435428.

It is an arithmetic number, because the mean of its divisors is an integer number (192373496).

Almost surely, 2^1291650428 is an apocalyptic number.

It is an amenable number.

1291650428 is a deficient number, since it is larger than the sum of its proper divisors (1016831524).

1291650428 is a wasteful number, since it uses less digits than its factorization.

1291650428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6870532 (or 6870530 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 1291650428 is about 35939.5385056625. The cubic root of 1291650428 is about 1089.0512823389.

The spelling of 1291650428 in words is "one billion, two hundred ninety-one million, six hundred fifty thousand, four hundred twenty-eight".