1391940637920 has 480 divisors, whose sum is σ = 5651396061696. Its totient is φ = 316047744000.

The previous prime is 1391940637861. The next prime is 1391940637949. The reversal of 1391940637920 is 297360491931.

It is a happy number.

1391940637920 is a `hidden beast` number, since 139 + 19 + 406 + 3 + 7 + 92 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 13647915 + ... + 13749525.

Almost surely, 2^{1391940637920} is an apocalyptic number.

1391940637920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1391940637920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2825698030848).

1391940637920 is an abundant number, since it is smaller than the sum of its proper divisors (4259455423776).

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

1391940637920 is a wasteful number, since it uses less digits than its factorization.

1391940637920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101796 (or 101779 counting only the distinct ones).

The product of its (nonzero) digits is 2204496, while the sum is 54.

The spelling of 1391940637920 in words is "one trillion, three hundred ninety-one billion, nine hundred forty million, six hundred thirty-seven thousand, nine hundred twenty".