20643699 has 8 divisors (see below), whose sum is σ = 27605200. Its totient is φ = 13722336.

The previous prime is 20643697. The next prime is 20643731. The reversal of 20643699 is 99634602.

It is a happy number.

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

It is not a de Polignac number, because 20643699 - 2¹ = 20643697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20643697) 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, 8812 + ... + 10905.

It is an arithmetic number, because the mean of its divisors is an integer number (3450650).

Almost surely, 2^20643699 is an apocalyptic number.

20643699 is a deficient number, since it is larger than the sum of its proper divisors (6961501).

20643699 is a wasteful number, since it uses less digits than its factorization.

20643699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20069.

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 20643699 is about 4543.5337568901. The cubic root of 20643699 is about 274.3231796773.

The spelling of 20643699 in words is "twenty million, six hundred forty-three thousand, six hundred ninety-nine".