217055957 has 2 divisors, whose sum is σ = 217055958. Its totient is φ = 217055956.

The previous prime is 217055941. The next prime is 217055963. The reversal of 217055957 is 759550712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194909521 + 22146436 = 13961^2 + 4706^2 .

It is a cyclic number.

It is not a de Polignac number, because 217055957 - 2⁴ = 217055941 is a prime.

It is a super-2 number, since 2×217055957² = 94226576938371698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217055977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108527978 + 108527979.

It is an arithmetic number, because the mean of its divisors is an integer number (108527979).

Almost surely, 2^217055957 is an apocalyptic number.

It is an amenable number.

217055957 is a deficient number, since it is larger than the sum of its proper divisors (1).

217055957 is an equidigital number, since it uses as much as digits as its factorization.

217055957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110250, while the sum is 41.

The square root of 217055957 is about 14732.8190445685. The cubic root of 217055957 is about 600.9761489903.

The spelling of 217055957 in words is "two hundred seventeen million, fifty-five thousand, nine hundred fifty-seven".