218148957 has 20 divisors (see below), whose sum is σ = 350945980. Its totient is φ = 134244864.

The previous prime is 218148907. The next prime is 218148967. The reversal of 218148957 is 759841812.

It can be written as a sum of positive squares in 2 ways, for example, as 145660761 + 72488196 = 12069^2 + 8514^2 .

It is not a de Polignac number, because 218148957 - 2¹⁰ = 218147933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218148907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 102532 + ... + 104637.

It is an arithmetic number, because the mean of its divisors is an integer number (17547299).

Almost surely, 2^218148957 is an apocalyptic number.

218148957 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

218148957 is a deficient number, since it is larger than the sum of its proper divisors (132797023).

218148957 is a wasteful number, since it uses less digits than its factorization.

218148957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207194 (or 207185 counting only the distinct ones).

The product of its digits is 161280, while the sum is 45.

The square root of 218148957 is about 14769.8665193698. The cubic root of 218148957 is about 601.9832125575.

The spelling of 218148957 in words is "two hundred eighteen million, one hundred forty-eight thousand, nine hundred fifty-seven".