217380972 has 24 divisors (see below), whose sum is σ = 537059376. Its totient is φ = 68197888.

The previous prime is 217380967. The next prime is 217380979. The reversal of 217380972 is 279083712.

It is a self number, because there is not a number n which added to its sum of digits gives 217380972.

It is not an unprimeable number, because it can be changed into a prime (217380979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 532593 + ... + 533000.

It is an arithmetic number, because the mean of its divisors is an integer number (22377474).

Almost surely, 2^217380972 is an apocalyptic number.

It is an amenable number.

217380972 is an abundant number, since it is smaller than the sum of its proper divisors (319678404).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217380972 is a wasteful number, since it uses less digits than its factorization.

217380972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1065617 (or 1065615 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 39.

The square root of 217380972 is about 14743.8452243640. The cubic root of 217380972 is about 601.2759623876.

The spelling of 217380972 in words is "two hundred seventeen million, three hundred eighty thousand, nine hundred seventy-two".