20690999 has 8 divisors (see below), whose sum is σ = 23738880. Its totient is φ = 17666136.

The previous prime is 20690993. The next prime is 20691001. The reversal of 20690999 is 99909602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20690999 - 2⁴ = 20690983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20690993) 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, 3779 + ... + 7460.

It is an arithmetic number, because the mean of its divisors is an integer number (2967360).

Almost surely, 2^20690999 is an apocalyptic number.

20690999 is a deficient number, since it is larger than the sum of its proper divisors (3047881).

20690999 is a wasteful number, since it uses less digits than its factorization.

20690999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11509.

The product of its (nonzero) digits is 78732, while the sum is 44.

The square root of 20690999 is about 4548.7359782691. The cubic root of 20690999 is about 274.5325347440.

The spelling of 20690999 in words is "twenty million, six hundred ninety thousand, nine hundred ninety-nine".