20869993 has 4 divisors (see below), whose sum is σ = 21777408. Its totient is φ = 19962580.

The previous prime is 20869987. The next prime is 20870023. The reversal of 20869993 is 39996802.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 20869993 - 2²¹ = 18772841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20869393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 453673 + ... + 453718.

It is an arithmetic number, because the mean of its divisors is an integer number (5444352).

Almost surely, 2^20869993 is an apocalyptic number.

20869993 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

20869993 is a deficient number, since it is larger than the sum of its proper divisors (907415).

20869993 is an equidigital number, since it uses as much as digits as its factorization.

20869993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 907414.

The product of its (nonzero) digits is 209952, while the sum is 46.

The square root of 20869993 is about 4568.3687460624. The cubic root of 20869993 is about 275.3219062354.

The spelling of 20869993 in words is "twenty million, eight hundred sixty-nine thousand, nine hundred ninety-three".