1393637521920 has 960 divisors, whose sum is σ = 5522732772480. Its totient is φ = 297887858688.

The previous prime is 1393637521847. The next prime is 1393637521931. The reversal of 1393637521920 is 291257363931.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1145141152 + ... + 1145142368.

It is an arithmetic number, because the mean of its divisors is an integer number (5752846638).

Almost surely, 2^{1393637521920} is an apocalyptic number.

1393637521920 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 1393637521920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2761366386240).

1393637521920 is an abundant number, since it is smaller than the sum of its proper divisors (4129095250560).

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

1393637521920 is a wasteful number, since it uses less digits than its factorization.

1393637521920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1453 (or 1430 counting only the distinct ones).

The product of its (nonzero) digits is 1837080, while the sum is 51.

The spelling of 1393637521920 in words is "one trillion, three hundred ninety-three billion, six hundred thirty-seven million, five hundred twenty-one thousand, nine hundred twenty".