20501866855 has 8 divisors (see below), whose sum is σ = 24779235600. Its totient is φ = 16283496576.

The previous prime is 20501866811. The next prime is 20501866859. The reversal of 20501866855 is 55866810502.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20501866855 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20501866859) 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, 14748850 + ... + 14750239.

It is an arithmetic number, because the mean of its divisors is an integer number (3097404450).

Almost surely, 2^20501866855 is an apocalyptic number.

20501866855 is a deficient number, since it is larger than the sum of its proper divisors (4277368745).

20501866855 is a wasteful number, since it uses less digits than its factorization.

20501866855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29499233.

The product of its (nonzero) digits is 576000, while the sum is 46.

The spelling of 20501866855 in words is "twenty billion, five hundred one million, eight hundred sixty-six thousand, eight hundred fifty-five".