20690929 has 4 divisors (see below), whose sum is σ = 23646784. Its totient is φ = 17735076.

The previous prime is 20690927. The next prime is 20690939. The reversal of 20690929 is 92909602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92909602 = 2 ⋅46454801.

It is a cyclic number.

It is not a de Polignac number, because 20690929 - 2¹ = 20690927 is a prime.

It is a super-2 number, since 2×20690929² = 856229085766082, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20690927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1477917 + ... + 1477930.

It is an arithmetic number, because the mean of its divisors is an integer number (5911696).

Almost surely, 2^20690929 is an apocalyptic number.

It is an amenable number.

20690929 is a deficient number, since it is larger than the sum of its proper divisors (2955855).

20690929 is an equidigital number, since it uses as much as digits as its factorization.

20690929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2955854.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 20690929 is about 4548.7282838174. The cubic root of 20690929 is about 274.5322251521.

The spelling of 20690929 in words is "twenty million, six hundred ninety thousand, nine hundred twenty-nine".