217470947 has 2 divisors, whose sum is σ = 217470948. Its totient is φ = 217470946.

The previous prime is 217470901. The next prime is 217470961. The reversal of 217470947 is 749074712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 217470947 - 2²⁶ = 150362083 is a prime.

It is a super-2 number, since 2×217470947² = 94587225578153618, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (217470247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108735473 + 108735474.

It is an arithmetic number, because the mean of its divisors is an integer number (108735474).

Almost surely, 2^217470947 is an apocalyptic number.

217470947 is a deficient number, since it is larger than the sum of its proper divisors (1).

217470947 is an equidigital number, since it uses as much as digits as its factorization.

217470947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 98784, while the sum is 41.

The square root of 217470947 is about 14746.8961819089. The cubic root of 217470947 is about 601.3589079215.

The spelling of 217470947 in words is "two hundred seventeen million, four hundred seventy thousand, nine hundred forty-seven".