191920406 has 16 divisors (see below), whose sum is σ = 311224560. Its totient is φ = 88452000.

The previous prime is 191920403. The next prime is 191920409. The reversal of 191920406 is 604029191.

191920406 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (191920403) and next prime (191920409).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191920403) 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, 66845 + ... + 69656.

It is an arithmetic number, because the mean of its divisors is an integer number (19451535).

Almost surely, 2^191920406 is an apocalyptic number.

191920406 is a deficient number, since it is larger than the sum of its proper divisors (119304154).

191920406 is a wasteful number, since it uses less digits than its factorization.

191920406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136559.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 191920406 is about 13853.5340617476. The cubic root of 191920406 is about 576.8200987627.

Adding to 191920406 its reverse (604029191), we get a palindrome (795949597).

The spelling of 191920406 in words is "one hundred ninety-one million, nine hundred twenty thousand, four hundred six".