1391781156 has 12 divisors (see below), whose sum is σ = 3247489392. Its totient is φ = 463927048.

The previous prime is 1391781119. The next prime is 1391781191. The reversal of 1391781156 is 6511871931.

It is a tau number, because it is divible by the number of its divisors (12).

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, 57990870 + ... + 57990893.

It is an arithmetic number, because the mean of its divisors is an integer number (270624116).

Almost surely, 2^1391781156 is an apocalyptic number.

It is an amenable number.

1391781156 is an abundant number, since it is smaller than the sum of its proper divisors (1855708236).

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

1391781156 is a wasteful number, since it uses less digits than its factorization.

1391781156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115981770 (or 115981768 counting only the distinct ones).

The product of its digits is 45360, while the sum is 42.

The square root of 1391781156 is about 37306.5832796304. The cubic root of 1391781156 is about 1116.4955180583.

The spelling of 1391781156 in words is "one billion, three hundred ninety-one million, seven hundred eighty-one thousand, one hundred fifty-six".