20931951896617 has 8 divisors (see below), whose sum is σ = 21096883039232. Its totient is φ = 20767022514000.

The previous prime is 20931951896593. The next prime is 20931951896623. The reversal of 20931951896617 is 71669815913902.

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-20931951896617 is a prime.

It is a super-2 number, since 2×20931951896617² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20931951896417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34042567 + ... + 34651987.

It is an arithmetic number, because the mean of its divisors is an integer number (2637110379904).

Almost surely, 2^{20931951896617} is an apocalyptic number.

It is an amenable number.

20931951896617 is a deficient number, since it is larger than the sum of its proper divisors (164931142615).

20931951896617 is a wasteful number, since it uses less digits than its factorization.

20931951896617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879999.

The product of its (nonzero) digits is 44089920, while the sum is 67.

The spelling of 20931951896617 in words is "twenty trillion, nine hundred thirty-one billion, nine hundred fifty-one million, eight hundred ninety-six thousand, six hundred seventeen".