20157955406217 has 16 divisors (see below), whose sum is σ = 30826980789760. Its totient is φ = 13005132519600.

The previous prime is 20157955406203. The next prime is 20157955406219. The reversal of 20157955406217 is 71260455975102.

20157955406217 is a `hidden beast` number, since 2 + 0 + 1 + 5 + 7 + 9 + 5 + 5 + 4 + 0 + 621 + 7 = 666.

It is not a de Polignac number, because 20157955406217 - 2¹⁰ = 20157955405193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20157955406219) 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, 12041788534 + ... + 12041790207.

It is an arithmetic number, because the mean of its divisors is an integer number (1926686299360).

Almost surely, 2^{20157955406217} is an apocalyptic number.

20157955406217 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20157955406217 is a deficient number, since it is larger than the sum of its proper divisors (10669025383543).

20157955406217 is a wasteful number, since it uses less digits than its factorization.

20157955406217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24083578781 (or 24083578775 counting only the distinct ones).

The product of its (nonzero) digits is 5292000, while the sum is 54.

The spelling of 20157955406217 in words is "twenty trillion, one hundred fifty-seven billion, nine hundred fifty-five million, four hundred six thousand, two hundred seventeen".