1326261391 has 24 divisors (see below), whose sum is σ = 1670794944. Its totient is φ = 1043461440.

The previous prime is 1326261383. The next prime is 1326261421. The reversal of 1326261391 is 1931626231.

It is not a de Polignac number, because 1326261391 - 2³ = 1326261383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1326261301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 109546 + ... + 121048.

It is an arithmetic number, because the mean of its divisors is an integer number (69616456).

Almost surely, 2^1326261391 is an apocalyptic number.

1326261391 is a deficient number, since it is larger than the sum of its proper divisors (344533553).

1326261391 is a wasteful number, since it uses less digits than its factorization.

1326261391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11711 (or 11704 counting only the distinct ones).

The product of its digits is 11664, while the sum is 34.

The square root of 1326261391 is about 36417.8718625897. The cubic root of 1326261391 is about 1098.6930458419.

The spelling of 1326261391 in words is "one billion, three hundred twenty-six million, two hundred sixty-one thousand, three hundred ninety-one".