218136828 has 72 divisors (see below), whose sum is σ = 637653072. Its totient is φ = 57528576.

The previous prime is 218136803. The next prime is 218136833. The reversal of 218136828 is 828631812.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6625 + ... + 21912.

Almost surely, 2^218136828 is an apocalyptic number.

218136828 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

218136828 is an abundant number, since it is smaller than the sum of its proper divisors (419516244).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218136828 is a wasteful number, since it uses less digits than its factorization.

218136828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28571 (or 28562 counting only the distinct ones).

The product of its digits is 36864, while the sum is 39.

The square root of 218136828 is about 14769.4559141493. The cubic root of 218136828 is about 601.9720556706.

The spelling of 218136828 in words is "two hundred eighteen million, one hundred thirty-six thousand, eight hundred twenty-eight".