1991930427093 has 8 divisors (see below), whose sum is σ = 2727688512928. Its totient is φ = 1292062979664.

The previous prime is 1991930427077. The next prime is 1991930427209. The reversal of 1991930427093 is 3907240391991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1991930427093 - 2⁴ = 1991930427077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991930427493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8972659471 + ... + 8972659692.

It is an arithmetic number, because the mean of its divisors is an integer number (340961064116).

Almost surely, 2^{1991930427093} is an apocalyptic number.

It is an amenable number.

1991930427093 is a deficient number, since it is larger than the sum of its proper divisors (735758085835).

1991930427093 is a wasteful number, since it uses less digits than its factorization.

1991930427093 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17945319203.

The product of its (nonzero) digits is 3306744, while the sum is 57.

The spelling of 1991930427093 in words is "one trillion, nine hundred ninety-one billion, nine hundred thirty million, four hundred twenty-seven thousand, ninety-three".