217728024785668 has 12 divisors (see below), whose sum is σ = 389885067639760. Its totient is φ = 106332291174312.

The previous prime is 217728024785639. The next prime is 217728024785731. The reversal of 217728024785668 is 866587420827712.

It is a self number, because there is not a number n which added to its sum of digits gives 217728024785668.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 632930304438 + ... + 632930304781.

Almost surely, 2^{217728024785668} is an apocalyptic number.

It is an amenable number.

217728024785668 is a deficient number, since it is larger than the sum of its proper divisors (172157042854092).

217728024785668 is a wasteful number, since it uses less digits than its factorization.

217728024785668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1265860609266 (or 1265860609264 counting only the distinct ones).

The product of its (nonzero) digits is 1011548160, while the sum is 73.

The spelling of 217728024785668 in words is "two hundred seventeen trillion, seven hundred twenty-eight billion, twenty-four million, seven hundred eighty-five thousand, six hundred sixty-eight".