1930990391 has 4 divisors (see below), whose sum is σ = 2106534984. Its totient is φ = 1755445800.

The previous prime is 1930990381. The next prime is 1930990427.

1930990391 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1930990391 - 2¹⁰ = 1930989367 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 (1930990381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87772280 + ... + 87772301.

It is an arithmetic number, because the mean of its divisors is an integer number (526633746).

Almost surely, 2^1930990391 is an apocalyptic number.

1930990391 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1930990391 is a deficient number, since it is larger than the sum of its proper divisors (175544593).

1930990391 is a wasteful number, since it uses less digits than its factorization.

1930990391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175544592.

The product of its (nonzero) digits is 59049, while the sum is 44.

The square root of 1930990391 is about 43943.0357508445. The cubic root of 1930990391 is about 1245.2599987095.

The spelling of 1930990391 in words is "one billion, nine hundred thirty million, nine hundred ninety thousand, three hundred ninety-one".