20399273 has 4 divisors (see below), whose sum is σ = 20601348. Its totient is φ = 20197200.

The previous prime is 20399261. The next prime is 20399279. The reversal of 20399273 is 37299302.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13778944 + 6620329 = 3712^2 + 2573^2 .

It is a cyclic number.

It is not a de Polignac number, because 20399273 - 2⁴ = 20399257 is a prime.

It is a super-2 number, since 2×20399273² = 832260677857058, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20399279) 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, 100886 + ... + 101087.

It is an arithmetic number, because the mean of its divisors is an integer number (5150337).

Almost surely, 2^20399273 is an apocalyptic number.

It is an amenable number.

20399273 is a deficient number, since it is larger than the sum of its proper divisors (202075).

20399273 is a wasteful number, since it uses less digits than its factorization.

20399273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202074.

The product of its (nonzero) digits is 20412, while the sum is 35.

The square root of 20399273 is about 4516.5554352847. Note that the first 3 decimals coincide. The cubic root of 20399273 is about 273.2361957363.

The spelling of 20399273 in words is "twenty million, three hundred ninety-nine thousand, two hundred seventy-three".