217787020972 has 24 divisors (see below), whose sum is σ = 403427908800. Its totient is φ = 102585941136.

The previous prime is 217787020951. The next prime is 217787021003. The reversal of 217787020972 is 279020787712.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7990918 + ... + 8018125.

It is an arithmetic number, because the mean of its divisors is an integer number (16809496200).

Almost surely, 2^217787020972 is an apocalyptic number.

It is an amenable number.

217787020972 is a deficient number, since it is larger than the sum of its proper divisors (185640887828).

217787020972 is a wasteful number, since it uses less digits than its factorization.

217787020972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16009245 (or 16009243 counting only the distinct ones).

The product of its (nonzero) digits is 1382976, while the sum is 52.

The spelling of 217787020972 in words is "two hundred seventeen billion, seven hundred eighty-seven million, twenty thousand, nine hundred seventy-two".