20690055987 has 8 divisors (see below), whose sum is σ = 27660701904. Its totient is φ = 13756390368.

The previous prime is 20690055977. The next prime is 20690056007. The reversal of 20690055987 is 78955009602.

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 20690055987 - 2⁶ = 20690055923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20690055977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9243768 + ... + 9246005.

It is an arithmetic number, because the mean of its divisors is an integer number (3457587738).

Almost surely, 2^20690055987 is an apocalyptic number.

20690055987 is a deficient number, since it is larger than the sum of its proper divisors (6970645917).

20690055987 is a wasteful number, since it uses less digits than its factorization.

20690055987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18490149.

The product of its (nonzero) digits is 1360800, while the sum is 51.

The spelling of 20690055987 in words is "twenty billion, six hundred ninety million, fifty-five thousand, nine hundred eighty-seven".