1391221340 has 12 divisors (see below), whose sum is σ = 2921564856. Its totient is φ = 556488528.

The previous prime is 1391221297. The next prime is 1391221343. The reversal of 1391221340 is 431221931.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1391221343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34780514 + ... + 34780553.

It is an arithmetic number, because the mean of its divisors is an integer number (243463738).

Almost surely, 2^1391221340 is an apocalyptic number.

1391221340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1391221340 is an abundant number, since it is smaller than the sum of its proper divisors (1530343516).

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

1391221340 is a wasteful number, since it uses less digits than its factorization.

1391221340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69561076 (or 69561074 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 1391221340 is about 37299.0796133095. The cubic root of 1391221340 is about 1116.3458020217.

The spelling of 1391221340 in words is "one billion, three hundred ninety-one million, two hundred twenty-one thousand, three hundred forty".