1391974840 has 64 divisors (see below), whose sum is σ = 3161410560. Its totient is φ = 551583360.

The previous prime is 1391974811. The next prime is 1391974847. The reversal of 1391974840 is 484791931.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1391974847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3229425 + ... + 3229855.

It is an arithmetic number, because the mean of its divisors is an integer number (49397040).

Almost surely, 2^1391974840 is an apocalyptic number.

1391974840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1391974840 is an abundant number, since it is smaller than the sum of its proper divisors (1769435720).

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

1391974840 is a wasteful number, since it uses less digits than its factorization.

1391974840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1012 (or 1008 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 1391974840 is about 37309.1790314394. The cubic root of 1391974840 is about 1116.5473071600.

The spelling of 1391974840 in words is "one billion, three hundred ninety-one million, nine hundred seventy-four thousand, eight hundred forty".