20305699 has 4 divisors (see below), whose sum is σ = 21374440. Its totient is φ = 19236960.

The previous prime is 20305693. The next prime is 20305777. The reversal of 20305699 is 99650302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99650302 = 2 ⋅49825151.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20305699 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20305693) 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, 534342 + ... + 534379.

It is an arithmetic number, because the mean of its divisors is an integer number (5343610).

Almost surely, 2^20305699 is an apocalyptic number.

20305699 is a deficient number, since it is larger than the sum of its proper divisors (1068741).

20305699 is a wasteful number, since it uses less digits than its factorization.

20305699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1068740.

The product of its (nonzero) digits is 14580, while the sum is 34.

The square root of 20305699 is about 4506.1845279571. The cubic root of 20305699 is about 272.8177658256.

The spelling of 20305699 in words is "twenty million, three hundred five thousand, six hundred ninety-nine".