1291040156 has 12 divisors (see below), whose sum is σ = 2582080368. Its totient is φ = 553302912.

The previous prime is 1291040143. The next prime is 1291040189. The reversal of 1291040156 is 6510401921.

1291040156 is an admirable number.

It is a congruent number.

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, 23054261 + ... + 23054316.

It is an arithmetic number, because the mean of its divisors is an integer number (215173364).

Almost surely, 2^1291040156 is an apocalyptic number.

It is an amenable number.

1291040156 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1291040156 is a wasteful number, since it uses less digits than its factorization.

1291040156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46108588 (or 46108586 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 1291040156 is about 35931.0472432964. The cubic root of 1291040156 is about 1088.8797389686.

The spelling of 1291040156 in words is "one billion, two hundred ninety-one million, forty thousand, one hundred fifty-six".