1391955642 has 144 divisors (see below), whose sum is σ = 3900884832. Its totient is φ = 354594240.

The previous prime is 1391955629. The next prime is 1391955647. The reversal of 1391955642 is 2465591931.

1391955642 is a `hidden beast` number, since 1 + 3 + 91 + 9 + 556 + 4 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (1391955647) 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 71 ways as a sum of consecutive naturals, for example, 512853 + ... + 515559.

It is an arithmetic number, because the mean of its divisors is an integer number (27089478).

Almost surely, 2^1391955642 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1391955642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1950442416).

1391955642 is an abundant number, since it is smaller than the sum of its proper divisors (2508929190).

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

1391955642 is a wasteful number, since it uses less digits than its factorization.

1391955642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2793 (or 2783 counting only the distinct ones).

The product of its digits is 291600, while the sum is 45.

The square root of 1391955642 is about 37308.9217480216. The cubic root of 1391955642 is about 1116.5421740276.

The spelling of 1391955642 in words is "one billion, three hundred ninety-one million, nine hundred fifty-five thousand, six hundred forty-two".