1991793403306 has 16 divisors (see below), whose sum is σ = 3415462462080. Its totient is φ = 853385873040.

The previous prime is 1991793403283. The next prime is 1991793403309. The reversal of 1991793403306 is 6033043971991.

It is a super-2 number, since 2×1991793403306² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1991793403309) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19937665 + ... + 20037316.

It is an arithmetic number, because the mean of its divisors is an integer number (213466403880).

Almost surely, 2^{1991793403306} is an apocalyptic number.

1991793403306 is a deficient number, since it is larger than the sum of its proper divisors (1423669058774).

1991793403306 is a wasteful number, since it uses less digits than its factorization.

1991793403306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39978549.

The product of its (nonzero) digits is 3306744, while the sum is 55.

The spelling of 1991793403306 in words is "one trillion, nine hundred ninety-one billion, seven hundred ninety-three million, four hundred three thousand, three hundred six".