216771137 has 6 divisors (see below), whose sum is σ = 238269234. Its totient is φ = 197064560.

The previous prime is 216771109. The next prime is 216771161. The reversal of 216771137 is 731177612.

216771137 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 146143921 + 70627216 = 12089^2 + 8404^2 .

It is not a de Polignac number, because 216771137 - 2⁶ = 216771073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216771097 and 216771106.

It is not an unprimeable number, because it can be changed into a prime (216771167) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 895628 + ... + 895869.

It is an arithmetic number, because the mean of its divisors is an integer number (39711539).

Almost surely, 2^216771137 is an apocalyptic number.

It is an amenable number.

216771137 is a deficient number, since it is larger than the sum of its proper divisors (21498097).

216771137 is a wasteful number, since it uses less digits than its factorization.

216771137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1791519 (or 1791508 counting only the distinct ones).

The product of its digits is 12348, while the sum is 35.

The square root of 216771137 is about 14723.1496969908. The cubic root of 216771137 is about 600.7131677245.

The spelling of 216771137 in words is "two hundred sixteen million, seven hundred seventy-one thousand, one hundred thirty-seven".