19913121395390 has 32 divisors (see below), whose sum is σ = 38947225559040. Its totient is φ = 7302604788000.

The previous prime is 19913121395389. The next prime is 19913121395399. The reversal of 19913121395390 is 9359312131991.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19913121395399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1690411886 + ... + 1690423665.

It is an arithmetic number, because the mean of its divisors is an integer number (1217100798720).

Almost surely, 2^{19913121395390} is an apocalyptic number.

19913121395390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19913121395390 is a deficient number, since it is larger than the sum of its proper divisors (19034104163650).

19913121395390 is a wasteful number, since it uses less digits than its factorization.

19913121395390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3380835608.

The product of its (nonzero) digits is 1771470, while the sum is 56.

The spelling of 19913121395390 in words is "nineteen trillion, nine hundred thirteen billion, one hundred twenty-one million, three hundred ninety-five thousand, three hundred ninety".