20699699 has 4 divisors (see below), whose sum is σ = 20721864. Its totient is φ = 20677536.

The previous prime is 20699671. The next prime is 20699713. The reversal of 20699699 is 99699602.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20699699 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20699639) 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, 9617 + ... + 11570.

It is an arithmetic number, because the mean of its divisors is an integer number (5180466).

Almost surely, 2^20699699 is an apocalyptic number.

20699699 is a deficient number, since it is larger than the sum of its proper divisors (22165).

20699699 is an equidigital number, since it uses as much as digits as its factorization.

20699699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22164.

The product of its (nonzero) digits is 472392, while the sum is 50.

The square root of 20699699 is about 4549.6921873903. The cubic root of 20699699 is about 274.5710071634.

The spelling of 20699699 in words is "twenty million, six hundred ninety-nine thousand, six hundred ninety-nine".