19131906 has 16 divisors (see below), whose sum is σ = 39927744. Its totient is φ = 6099984.

The previous prime is 19131899. The next prime is 19131943. The reversal of 19131906 is 60913191.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69181 + ... + 69456.

It is an arithmetic number, because the mean of its divisors is an integer number (2495484).

Almost surely, 2^19131906 is an apocalyptic number.

19131906 is an abundant number, since it is smaller than the sum of its proper divisors (20795838).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19131906 is a wasteful number, since it uses less digits than its factorization.

19131906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138665.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 19131906 is about 4374.0034293539. The cubic root of 19131906 is about 267.4562469565.

Subtracting from 19131906 its sum of digits (30), we obtain a square (19131876 = 4374²).

The spelling of 19131906 in words is "nineteen million, one hundred thirty-one thousand, nine hundred six".