20690680905 has 48 divisors (see below), whose sum is σ = 37701780480. Its totient is φ = 10883818368.

The previous prime is 20690680903. The next prime is 20690680937. The reversal of 20690680905 is 50908609602.

It is not a de Polignac number, because 20690680905 - 2¹ = 20690680903 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20690680903) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 27945 + ... + 205334.

It is an arithmetic number, because the mean of its divisors is an integer number (785453760).

Almost surely, 2^20690680905 is an apocalyptic number.

It is an amenable number.

20690680905 is a deficient number, since it is larger than the sum of its proper divisors (17011099575).

20690680905 is an equidigital number, since it uses as much as digits as its factorization.

20690680905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233372 (or 233360 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 20690680905 in words is "twenty billion, six hundred ninety million, six hundred eighty thousand, nine hundred five".