217998040305 has 16 divisors (see below), whose sum is σ = 348926448960. Its totient is φ = 116222426688.

The previous prime is 217998040291. The next prime is 217998040307. The reversal of 217998040305 is 503040899712.

It is not a de Polignac number, because 217998040305 - 2⁸ = 217998040049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (217998040307) 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, 2657935 + ... + 2738724.

It is an arithmetic number, because the mean of its divisors is an integer number (21807903060).

Almost surely, 2^217998040305 is an apocalyptic number.

It is an amenable number.

217998040305 is a deficient number, since it is larger than the sum of its proper divisors (130928408655).

217998040305 is a wasteful number, since it uses less digits than its factorization.

217998040305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5399360.

The product of its (nonzero) digits is 544320, while the sum is 48.

The spelling of 217998040305 in words is "two hundred seventeen billion, nine hundred ninety-eight million, forty thousand, three hundred five".