19729906 has 32 divisors (see below), whose sum is σ = 35831808. Its totient is φ = 7964880.

The previous prime is 19729903. The next prime is 19729907. The reversal of 19729906 is 60992791.

19729906 = 109² + 110² + ... + 392².

It is not an unprimeable number, because it can be changed into a prime (19729903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22431 + ... + 23293.

It is an arithmetic number, because the mean of its divisors is an integer number (1119744).

Almost surely, 2^19729906 is an apocalyptic number.

19729906 is a deficient number, since it is larger than the sum of its proper divisors (16101902).

19729906 is a wasteful number, since it uses less digits than its factorization.

19729906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 966.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 19729906 is about 4441.8358817048. The cubic root of 19729906 is about 270.2143063060.

It can be divided in two parts, 197 and 29906, that added together give a palindrome (30103).

The spelling of 19729906 in words is "nineteen million, seven hundred twenty-nine thousand, nine hundred six".