1291906216 has 16 divisors (see below), whose sum is σ = 2549815200. Its totient is φ = 611955504.

The previous prime is 1291906193. The next prime is 1291906229. The reversal of 1291906216 is 6126091921.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4249540 + ... + 4249843.

It is an arithmetic number, because the mean of its divisors is an integer number (159363450).

Almost surely, 2^1291906216 is an apocalyptic number.

It is an amenable number.

1291906216 is a deficient number, since it is larger than the sum of its proper divisors (1257908984).

1291906216 is a wasteful number, since it uses less digits than its factorization.

1291906216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8499408 (or 8499404 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 1291906216 is about 35943.0969172107. The cubic root of 1291906216 is about 1089.1231665622.

The spelling of 1291906216 in words is "one billion, two hundred ninety-one million, nine hundred six thousand, two hundred sixteen".