217442051 has 2 divisors, whose sum is σ = 217442052. Its totient is φ = 217442050.

The previous prime is 217442047. The next prime is 217442063. The reversal of 217442051 is 150244712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 217442051 - 2² = 217442047 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 217442051.

It is not a weakly prime, because it can be changed into another prime (217442021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108721025 + 108721026.

It is an arithmetic number, because the mean of its divisors is an integer number (108721026).

Almost surely, 2^217442051 is an apocalyptic number.

217442051 is a deficient number, since it is larger than the sum of its proper divisors (1).

217442051 is an equidigital number, since it uses as much as digits as its factorization.

217442051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 217442051 is about 14745.9164177748. The cubic root of 217442051 is about 601.3322719702.

Adding to 217442051 its reverse (150244712), we get a palindrome (367686763).

The spelling of 217442051 in words is "two hundred seventeen million, four hundred forty-two thousand, fifty-one".