20688711 has 16 divisors (see below), whose sum is σ = 29613024. Its totient is φ = 12801024.

The previous prime is 20688697. The next prime is 20688713. The reversal of 20688711 is 11788602.

It is a happy number.

It is not a de Polignac number, because 20688711 - 2¹⁹ = 20164423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20688713) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 945 + ... + 6501.

It is an arithmetic number, because the mean of its divisors is an integer number (1850814).

Almost surely, 2^20688711 is an apocalyptic number.

20688711 is a deficient number, since it is larger than the sum of its proper divisors (8924313).

20688711 is a wasteful number, since it uses less digits than its factorization.

20688711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5650.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 20688711 is about 4548.4844728767. The cubic root of 20688711 is about 274.5224151489.

The spelling of 20688711 in words is "twenty million, six hundred eighty-eight thousand, seven hundred eleven".