216257957 has 2 divisors, whose sum is σ = 216257958. Its totient is φ = 216257956.

The previous prime is 216257947. The next prime is 216257963. The reversal of 216257957 is 759752612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 190053796 + 26204161 = 13786^2 + 5119^2 .

It is a cyclic number.

It is not a de Polignac number, because 216257957 - 2¹⁶ = 216192421 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216257917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108128978 + 108128979.

It is an arithmetic number, because the mean of its divisors is an integer number (108128979).

Almost surely, 2^216257957 is an apocalyptic number.

It is an amenable number.

216257957 is a deficient number, since it is larger than the sum of its proper divisors (1).

216257957 is an equidigital number, since it uses as much as digits as its factorization.

216257957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 264600, while the sum is 44.

The square root of 216257957 is about 14705.7117134806. The cubic root of 216257957 is about 600.2387540556.

The spelling of 216257957 in words is "two hundred sixteen million, two hundred fifty-seven thousand, nine hundred fifty-seven".