190921906 has 16 divisors (see below), whose sum is σ = 338581440. Its totient is φ = 79002000.

The previous prime is 190921903. The next prime is 190921909. The reversal of 190921906 is 609129091.

190921906 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 (190921903) and next prime (190921909).

It is not an unprimeable number, because it can be changed into a prime (190921903) 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, 234720 + ... + 235531.

It is an arithmetic number, because the mean of its divisors is an integer number (21161340).

Almost surely, 2^190921906 is an apocalyptic number.

190921906 is a deficient number, since it is larger than the sum of its proper divisors (147659534).

190921906 is a wasteful number, since it uses less digits than its factorization.

190921906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470289.

The product of its (nonzero) digits is 8748, while the sum is 37.

The square root of 190921906 is about 13817.4493304662. The cubic root of 190921906 is about 575.8180225835.

The spelling of 190921906 in words is "one hundred ninety million, nine hundred twenty-one thousand, nine hundred six".